vacuum aluminum brazing furnace

7/28/2019 Vacuum Aluminum Brazing Furnace

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INSTALLATION AND OPERATING INSTRUCTIONS

PV/TVACUUM ALUMINUM BRAZING FURNACE

Manual No. VBR7Z110F.LP101.002.002PV/T I N C O R P O R A T E DRancocas, N.J . 08073(609) 267-3933


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THIS INSTRUCTION MANUAL IS DESIGNED TO AID YOU, NOT ONLY IN THE INSTALLATION OF THISEQUIPMENT, BUT THROUGHOUT IT'S WORKING LIFE. HOW WELL IT AIDS YOU DEPENDS UPONHOW THOROUGHLY YOU READ AND MAKE REFERENCE TO IT. SINCE YOUR WARRANTY DOESNOT COVER DAMAGE RESULTING FROM ABUSE AND FROM ERRORS IN INSTALLATION, IT IS TO

YOUR ADVANTAGE TO READ THIS MANUAL AND ALL COMPONENT MANUALS INCLUDED WITH THISMANUAL, AS COMPREHENSIVELY AS POSSIBLE.

FURTHER ASSISTANCE IS AVAILABLE, IF NECESSARY, FROM THE FACTORY


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SAFETY CONSIDERATIONS

Read the following instructions and take all necessary precautions.

This sheet and the installation, operation and maintenance instructions can help you to operate this systemsafely and efficiently. Read them. Special operating considerations and precautions will be found in theoperating instructions.

Uninformed or careless operation of this system can result in poor performance, damage to the system orother property, serious bodily injury and possible death.

Users of this system should be alert to two levels of hazards identified by the following symbols:

Warnings are used when failure to observe instructions or p rocedurescould result in in jury or death.

Cautions are used when failure to observe instructions could result insignificant damage to equipment.


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SAFETY SUMMARY

The following are general safety precautions that are not related to any specific procedures. They arerecommended precautions that personnel must understand and apply during many phases of operation and

maintenance.

KEEP AWAY FROM LIVE CIRCUITS

Do not attempt to replace components or make adjustments inside the equipment with the high voltage supplyturned on.

DO NOT SERVICE OR ADJ UST ALONE

Under no circumstance should any person service or adjust the equipment except in the presence of someone who is capable of rendering aid.

USE SAFETY APPROVED EQUIPMENT

When cleaners or primers are being applied, approved explosion proof lamps, blowers, and other equipmentshall be used. Insure that fire fighting equipment is readily available and in working order. Keep cleaners inapproved containers and in minimum quantities. Discard soiled cleaning cloths into safety cans.

HIGH VOLTAGE is used in this equipment. Before working inside thisequipment, TURN THE POWER OFF.


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Table of Contents

1. INTRODUCTION ......................................................................................................................................................7

1.1 G ENERAL D ESCRIPTION .........................................................................................................................................7

2. INSPECTION & INSTALLATION..........................................................................................................................8

2.1 I NSPECTION ...........................................................................................................................................................8 2.2 I NSTALLATION & A SSEMBLY .................................................................................................................................8 2.3 S ERVICE C ONNECTIONS .........................................................................................................................................9

3. START-UP ................................................................................................................................................................10

3.1 I NITIAL ................................................................................................................................................................10 3.2 A UTOMATIC ........................................................................................................................................................12 3.3 M ANUAL .............................................................................................................................................................12

4. OPERATION............................................................................................................................................................13

4.1 A UTOMATIC ........................................................................................................................................................13 4.2 M ANUAL .............................................................................................................................................................15

5. HC900 NAVIGATION.............................................................................................................................................16

6. HC900 SETUP ..........................................................................................................................................................17

6.1 D OWNLOADING P ROGRAMS TO THE H ONEYWELL HC900 ...................................................................................17 6.2 L OADING P ROGRAMS ..........................................................................................................................................17 6.3 S ETUP O PTIONS ...................................................................................................................................................18 6.4 T REND S ELECTOR ................................................................................................................................................18 6.5 W ORK T/C S ELECT ..............................................................................................................................................19

7. HONEYWELL USER UTILITY ............................................................................................................................20

7.1 L OADING THE C ONTROLLER F ILE ........................................................................................................................20 7.2 R ECIPE E DITOR ....................................................................................................................................................21 7.3 P ROGRAMMING S ETPOINT P ROFILE FOR THE HC900 ...........................................................................................23 7.4 D ATA S TORAGE ...................................................................................................................................................27 7.5 HC900 E VENTS ...................................................................................................................................................30

8. SWITCHING FROM PID OPERATION TO MANUAL.....................................................................................31

9. AUTO TUNING........................................................................................................................................................32

10. BAKEOUT ............................................................................................................................................................32

11. INERT GAS OPERATION .................................................................................................................................32

12. CONTROL UTILITY ..........................................................................................................................................33

13. SHUT DOWN .......................................................................................................................................................34

13.1 A UTOMATIC ........................................................................................................................................................34 13.2 M ANUAL .............................................................................................................................................................34


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14. ALARMS...............................................................................................................................................................35

14.1 A LARM O VERVIEW ..............................................................................................................................................35 14.2 C RITICAL A LARMS ..............................................................................................................................................36 14.3 N ON -C RITICAL A LARMS ......................................................................................................................................39

15. PUMP & VALVE INTERLOCKS ......................................................................................................................40

15.1 R OUGH P UMP ......................................................................................................................................................40 15.2 V ACUUM B LOWER ...............................................................................................................................................40 15.3 R OUGH P UMP V ACUUM B REAK V ALVE ...............................................................................................................40 15.4 H OLD P UMP .........................................................................................................................................................40 15.5 H OLD P UMP V ACUUM B REAK V ALVE .................................................................................................................40 15.6 H OLD P UMP V ALVE .............................................................................................................................................41 15.7 D IFFUSION P UMP .................................................................................................................................................41 15.8 R OUGH V ALVE ....................................................................................................................................................41 15.9 F ORELINE V ALVE ................................................................................................................................................41 15.10 H IGH V ACUUM V ALVE ....................................................................................................................................42 15.11 V ACUUM B REAK V ALVE .................................................................................................................................42 15.12 H EAT ...............................................................................................................................................................42

16. PRECAUTIONS ...................................................................................................................................................43

17. TROUBLE SHOOTING AND MAINTENANCE .............................................................................................44

17.1 V ACUUM S YSTEM ................................................................................................................................................44 17.2 P OWER S UPPLY ...................................................................................................................................................45 17.3 S ENSORS ..............................................................................................................................................................46 17.4 I NSTRUMENTATION .............................................................................................................................................46 17.5 P ILOT L AMP T EST ................................................................................................................................................46 17.6 I NTERLOCKS AND A LARMS ..................................................................................................................................46 17.7 C OOLING .............................................................................................................................................................46 17.8 C ONTINUOUS M AINTENANCE C HECK L IST ..........................................................................................................47 17.9 S HIFT M AINTENANCE C HECK L IST ......................................................................................................................47 17.10 W EEKLY M AINTENANCE C HECK L IST .............................................................................................................47 17.11 M ONTHLY M AINTENANCE C HECK L IST ...........................................................................................................47 17.12 P ERIODIC M AINTENANCE C HECK L IST ............................................................................................................48

18. INSTRUMENT SETTINGS ................................................................................................................................49

18.1 O VER T EMP C ONTROLLER ...................................................................................................................................49 18.2 T ELEVAC M ODEL MM200...................................................................................................................................50


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1. INTRODUCTION

1.1 GENERAL DESCRIPTION

The PV/T Vacuum Brazer is a cold wall, batch type vacuum furnace designed expressly for fluxless vacuumbrazing of aluminum.

The furnace system consists of the following:

A water cooled cylindrical vacuum chamber with front and rear doors.

A modular hot zone that heats the work from six sides. The entire hot zone assembly is removable for easymaintenance of the heating elements.

A power supply with seven variable reactance transformers for independent control of heat output for each

zone.

A control panel for auto/manual operation of the furnace system with all necessary controls andinstrumentation.

A three stage vacuum pumping system.

A water cooling system for the furnace, pumps, and power supply.

The equipment is of heavy industrial quality to provide durability and reliable operation. The design followsNFPA, NEMA, and OSHA specifications as applicable. The furnace is primed and finish painted withmachinery enamel.

Controls:Controls and instrumentation for the system are housed in a two door NEMA 12, enclosure. This factoryassembled and wired control cabinet contains all the necessary push buttons, switches, indicating pilot lamps,control relays, motor starters, contactors, circuit breakers and marked terminal strips for connection of wiringbetween the panel and junction boxes on the furnace. Also included is a system graphic display, andinstrumentation for vacuum and temperature.

The control system is designed for automatic sequential operation of the vacuum pumping system withmanual operation override. All necessary safety interlocks are provided. After placing the vacuum pumps inoperation, actuation of a single push button initiates the fully automatic cycle. Control of the heat profile in thehot zone is accomplished by A Honeywell HC900 processor digital temperature controller. A separately wiredUDC-2500 furnace over-temperature controller is provided. The vacuum instrumentation includes a Televaccombination ionization gauge for reading high vacuum in the furnace chamber and a thermocouple typevacuum gauge with four active positions. These include; the furnace chamber, diffusion pump foreline,roughing line, and hold pump line. Adjustable set points are provided for automatic actuation of the vacuumvalves.


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2. INSPECTION & INSTALLATION

2.1 INSPECTION

Every effort is made to insure that the system is packed properly. However, rough and/or careless handling intransit occasionally results in shipping damage. In such cases the carrier is responsible for the damages.First carefully inspect the outside of all shipping containers for shipping damage. If shipping damage is found,stop and immediately contact the carrier. Save the shipping container and the packing materials if making adamage claim.

2.2 INSTALLATION & ASSEMBLY

2.2.1 Utilities

Control Panel Electric Supply .............................480 Volts / 100A / 3 Phase 60 HzFurnace Electric Supply ......................................480 Volts / 300A / 3 Phase 60 HzCompressed Air Supply.......................................2 cfm @ 80 to 120 psigOptional Inert Gas Supply....................................10 cfm @ 90 to 120 psig

City water:Mechanical pump.................................................3 gpmDiffusion pump .....................................................2 gpmVariable reactance transformers..........................6 gpmMake-up water .....................................................10 gpm

Total .....................................................................21 gpm

This equipment and its parts are big and heavy. Always use power assisted equipment and trained moving / installing personnel to avoid

dropping, slipping or overturning which could kill or seriously injure theinexperienced worker.


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2.3 S ERVICE CONNECTIONS

2.3.1 Power

A source of electrical power for the system should be brought into the main electrical control cabinet.Connect the three phase electric cables to the top of the control cabinet main circuit breaker located withinthis cabinet and connect the grounding conductor to the ground block. Consult the PV/T electrical schematic

for power requirements and wiring details.

2.3.2 Water

Water is required by the system to cool its various components. The water supplied to the system shouldhave a PH value of between 6.0 and 8.0 and a calcium carbonate concentration of less than 75 parts permillion (typical municipal drinking water quality). For applications of lower PH or greater hardness, waterconditioning may be required. Consult Water Circulation System and Water Schematic for waterrequirements and piping details.

2.3.3 Air

A source of compressed air is required by the system to operate the various pneumatic valves and cylinders.Connect a supply of air to the coupling provided on the top of the poppet valve. Air should be supplied at apressure between 80 and 120 psig with a minimum supply of 2 cfm.

2.3.4 Inert Gas

The optional Inert gas system requires a source of high purity grade inert gas preferably dry nitrogen or argonsupplied at a minimum of 90 PSI and can be supplied at a volume of 10 cfm. The inert gas supply line shouldbe diameter or larger. Remove the needle valve for gas backfill operations.

This equipment operates at HIGH VOLTAGES which are high enough tokill through electrical shock. Always break the primary circuits of thepower supp ly when direct access to an electrical cabinet is required.

The water used to cool the system can reach scalding temperatures.Touching or rupture of the cooling system can cause serious burns.


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3. S TART -UP

3.1 INITIAL To start up the system for the first time, first turn on all service connections, i.e. power, water, air, etc., at theirsource. Next turn on the power by turning on the main power disconnect switch, located on the rear of thecontrol cabinet. Turn on the control system power by extending the emergency stop mushroom and pressingthe ON push button located below the red POWER pilot lamp. This will turn on the instrument power andallow operation of the system.

3.1.1 Pump Rotation

At this time the mechanical vacuum pumps should be checked for proper rotation per their owners manual. To do so, first put the mode switch into the MANUAL position, then, one at a time, turn on each of themechanical pumps (Rough Pumps, Blowers, and Hold Pumps) with its push button and observe the pumpmotors direction of rotation. If it is incorrect, shut off the main power disconnect switch, open the door of the

control cabinet, and exchange any two of the wires leaving the motor starter connected to the pump inquestion. After changing the motor starter connection repeat the above procedure to confirm that rotation iscorrect.

The mechanical vacuum pumps are equipped wi th THREE PHASEMOTORS and their direction of rotation must be considered. Operating

these pumps in the wrong direction for pro longed periods can causesever damage to the pump.


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3.1.2 Instrument Configuration

Check relay set points accessed through SETUP on the Televac MM200 digital vacuum gauges. The settingsfor 1, 2, 3, and 4 should be as follows:

Televac MM-200 Relay Set point #1 operates with TC #1 and is factory set for 100 microns for its ON pointand 110 microns for the OFF set point. This TC monitors the furnace chamber. The relay setpoint is used asthe crossover point from rough to high vacuum and the time for chamber roughing vacuum alarm.

Televac MM-200 Relay Set point #2 operates with TC #3 and is factory set for 100 microns for its ON pointand 500 microns for the OFF set point. This TC monitors the diffusion pump foreline pressure. This relay isused to insure that the diffusion pump is always operating in a safe range. Before the diffusion pump can beturned on the foreline pressure must be below the ON set point. If the foreline pressure rises above the OFFset point, the pump will be shut off.

Televac MM-200 Relay Set point #3 operates with CC#1 and is factory set for 9 x 10 -5 Torr for its ON pointand 2 x 10 -4 Torr for the OFF set point. This Cold Cathode relay controls the vacuum starting point of theHC900 setpoint program and is also used as the vacuum alarm time to high vacuum setpoint.

Televac MM-200 Relay Set point #4 operates with CM#1 and is factory set for 600 Torr for its ON point and740 Torr for the OFF set point. This Capacitance Manometer relay controls the Inert Gas Pressure and mayalso be used as a hold for Process Vacuum.

Check that the Honeywell HC900 controller is configured per the Honeywell HC900 section 6 of this manual.

Once all of these steps have been taken the system is ready for normal Start-Up.


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3.2 AUTOMATIC

To start the system, first turn on the control power, put the mode switch in either the AUTOMATIC orMANUAL position and then depress the push button marked START UP. Upon doing so, the AUTO PUMPON pilot lamp will illuminate and the mechanical pumps will come on. Twelve seconds after the mechanicalpump comes on, the Foreline Valve and Hold Pump Valve will open to evacuate the Diffusion Pump. Fiveminutes after the foreline pressure reaches 100 microns the Diffusion Pump will come on. A Vacuum alarmwill trigger if the foreline pressure of 100 microns can not be reached within five minutes after the forelinevalve opens. A Vacuum Alarm will cause the start up sequence to halt. When the Diffusion Pump hasreached the selected operating temperature designated within the HC900 AUTO PUMP ON pilot lamp will goout, and the READY pilot lamp will come on.

3.3 MANUAL

To manually start the system proceed as follows:

Turn on the control and instrument power by extending the emergency stop mushroom and pressing the ONpush button located below the red POWER pilot lamp. This will turn on the instrument power and allowoperation of the system.

Turn the mode selector switch to the MANUAL position.

Depress the push buttons marked ROUGH PUMP and HOLD PUMP. Upon doing so the mechanical pumpswill come on.

Open the HOLD PUMP VALVE and the FORELINE VALVE with their push buttons. Observe the diffusionpump foreline pressure by turning the vacuum gauge's TC SELECT switch to the 3 position.

When the foreline pressure reaches 100 microns turn on the DIFFUSION PUMP with its push button andallow time for it to heat up. After the Diffusion Pump has reached operating temperature the READY pilotlamp will come on indicating that the system is ready to be operated manually or automatically.

Careless or improper operation o f the DIFFUSION PUMP can causeserious injury or death and damage to the equipment. The operator

shou ld read and fully understand the Installation, Operating, andMaintenance Instructions for the Varian Diffusion Pump before

attempting its operation.


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4. OPERATION

The system should normally be operated in the automatic mode. Operating in the manual mode should bedone only by qualified personnel since improper manual operation could be harmful to both the workload andthe system.

4.1 AUTOMATIC

Since all aspects of an automatic cycle are either user adjustable, through instrument set points, orprogrammable, through the Honeywell HC900, the system is extremely flexible. The following describes thepreparation for, and operation of an automatic cycle.

4.1.1 Preparation

Enter a program into the Honeywell HC900 (refer to the HC900 instruction manual for entering programsusing the HC900 keypad interface or section 7.3 of this manual for programming using a computer and theHoneywell user utility) While doing so, keep in mind that Events are being utilized to control various aspectsof the automatic cycle and must be programmed accordingly. Refer to Section 7.3.3 for example program.

Adjust the High Limit controller to a temperature 10 to 20 degrees above the highest soak set pointprogrammed on the HC900. If necessary reset this controller by pressing the RESET button located on itsface.

Adjust relay set point #3 associated with the Cold Cathode portion (station 7) of the digital vacuum gauge. These set points define the vacuum range for the automatic cycle to be permitted to run. The lower pressureON set point also enables the vacuum alarm. The higher pressure OFF set point will put the HC900 in hold,where it will stay until the lower set point is reached.

Check that the vacuum BLOWER is enabled by turning its selector switch to the AUTO.

Check that the WATER PUMP is on.


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4.1.2 Automatic Operation

After all preparations have been made, depress the push button marked Cycle START to initiate theautomatic cycle. Actual initiation of a cycle is dependent on the following conditions:

The system ready pilot lamp is on The rough pump is on The blower is enabled The hold pump is on The hold pump valve is open The diffusion pump is on The water pump is on The over temp limit controller has been reset The chamber doors are closedNo alarm conditions exist

If any of these conditions are not met nothing will happen when Cycle START is pressed. Once the cycle hasstarted, the Honeywell HC900 will start executing its user program, and the rough valve will open to beginevacuation of the chamber. When the pressure in the furnace chamber reaches crossover the rough valvewill close, the foreline valve will open, and then the high vacuum valve will open.

Note: While an automatic cycle is in progress, as indicated by the AUTO CY CLE pilot lamp being on,turning the mode switch or pressing any button, except Cycle STOP, will have no effect on the system. If it isdesired to go to the manual mode, first press Cycle STOP to abort the cycle, and then turn the mode switch tothe MANUAL position.

When the process ends the CYCLE COMPLETE pilot lamp will come on, the alarm bell will ring for three (3)seconds, and the HC900 will show ENDCYCLE. At this time the Cycle STOP button may be used to reset theHC900 and vent the furnace chamber. If the Cycle STOP button has not been pushed after sixty (60) minutesof Cycle Complete, and the chamber is not already in high vacuum, the system will automatically pump itself down.


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4.2 MANUAL

4.2.1 General

This system incorporates three manual modes. The normal "Safetied Manual" is indicated by the greenMANUAL pilot lamp being on. The second mode is "Auto Manual" and is indicated by the MANUAL andAUTO CYCLE pilot lamp being on. The third mode is "Unsafe Manual" and is indicated by the MANUAL pilotlamp flashing. In both the Safetied and Unsafe Manual modes, the system is operated by the Illuminatedpush buttons located on the graphic panel. The Auto Manual mode is operated by the amber push buttonsmarked Cycle START and Cycle STOP. Note that none of the events programmed on the HC900 will haveany effect on any of the manual modes. Also, the HC900 will not go into hold or run mode due to furnacepressure.

4.2.2 Manual Mode

Placing the Auto\Manual selector switch to the MANUAL position is the manual mode. In this mode thesystem will observe proper time delays between valves opening and closing regardless of how fast theoperator selects them. Such situations as having the Vacuum Break Valve and the Rough Valve open at thesame time are disallowed. All disallowed states are indicated by a flashing pilot lamp.

4.2.3 Semi Automatic

The Semi Automatic mode is reached by depressing either Cycle START or Cycle STOP for a duration of atleast 1 second while in Ready - Manual. Cycle START will automatically close all conflicting valves, and thencause the system to pump down and cross over into high vacuum. Pushing Cycle STOP will also close allconflicting valves, and open the vent valve until the chamber door opens. Pushing any of the manual pushbuttons except Heat, or going to the Unsafe Manual mode will abort the Auto Manual mode.

4.2.4 Unsafe Manual

The safeties of the normal manual mode can be over ridden by going into the Unsafe Manual mode. This isdone by simultaneously holding in the amber push buttons marked Cycle START and Cycle STOP andpushing the ALARM SILENCE pushbutton. Once this is done the MANUAL pilot lamp will flash. Repeatingthis process, or changing the position of the mode switch, will abort this mode.

Only qualifi ed personnel should operate the system in the UNSAFEMANUAL mode. In this mode the system will no t observe proper time

delays and/or disallowed states. Damage to the system and/or workload

can occur if proper time delays and/or sequencing are not observed.


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5. HC900 N AVIGATION This Section explains the HC900 keys.

5.1.1 Operator KeysFor other keys refer to the HC900 manual.

HC900 Keys

Menu Help

Alarm Acknowledge Auto/Manual

Detail Window Tab

Left Arrow Decrement

Increment Enter

Page Up Page Down

Function Key Numeric 0-9


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6. HC900 S ETUP

This Section will guide you in setting up the Honeywell HC900 to run an Automatic Brazing Cycle.

6.1 DOWNLOADING P ROGRAMS TO THE HONEYWELL HC900

Recipe Data Storage Settings Set Point Profile

The Programs can be downloaded by floppy disk or through serial communication.Once Downloaded the programs remain in non-volatile memory and can be loaded as the active workingprogram.Reference the HC900 Operations Manual and the Honeywell User Utility section 7 of this Manual.

6.2 LOADING P ROGRAMS

6.2.1 Recipe:Select Screen 8 Page 1 Load RecipeSelect the either the newly downloaded or existing recipe from the list by scrolling and entering your selection.

6.2.2 Storage Settings:If new Data Storage Settings were downloaded they need to be activated.Reference the HC900 Operations Manual to start new Data Storage Settings.

Once the Data Storage Settings are started a blank floppy disk can be initialized to record the data.

6.2.3 Set Point Profile:Select Screen 1 Page 1 ProgrammerScroll to Load and enterSelect the either the newly downloaded or existing Set Point Profile from the list by scrolling and entering yourselection.


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6.3 S ETUP OPTIONS Select Screen 8 Page 2 Set up Options

6.3.1 End ControllerSet for on to hold for the endpoint work thermocouples or off to disregard.When set to on the HC900 Program will go into a hold when event 5 is selected for the currant segment of any HC900 set point profile program, until the minimum number of endpoint thermocouples have reachedtheir Setpoint temperature designated in the HC900 recipe.

When set to off the HC900 will not hold for the endpoint thermocouples regardless if event 5 is selected forany segment of HC900 set point profile.

6.3.2 Vac Before CycleSelect from two pre-programmed settings 1VGSP3 or 1VGSP4.

This setting determines the Vacuum Pressure before the HC900 Process Starts. These settings use the relay setpoints of CH#3 and CH#4 of the Televac MM200.1VGSP3 is typically the High Vacuum setting and 1VGSP4 is the Rough Vacuum.

6.3.3 Tune ConstantsSelect Tune1 or Tune2

This setting will allow switching between two sets of tune constants.Example: use Tune1 for a normally loaded furnace and use Tune2 for a lightly loaded furnace.

6.3.4 Heat off SignalSelect Events, Cycle, Endpts or Manual

Events: Heat Power is controlled by the toggling of event #1 in the set point profile program.

Cycle: Heat Power will be on from when the HC900 set point profile program Run to End Cycle.

Endpts: Heat Power will be on from the HC900 set point profile program Run until the endpoint temperaturehas been achieved

Manual: Heat power will be controlled manually through the control utility. Reference the Control Utility section12 of this manual.

6.4 T REND S ELECTOR Select Screen 4 Page 2 Trend Selector

6.4.1 TrendingWhen the Trending Floppy disk has been initialized (reference the HC900 operations manual)Selectable ranges of data storage are possible. Select from the following settings.OFF: No TrendingCONT: Continuous trending when the HC900 power is applied.BATCH: Incremental Batch Trending determined by the Batch Trend Selector.


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6.4.2 Batch Trend SelectorChose the recording duration when Batch is selected from the trend selector (above).Cycle: recording from cycle start to chamber vacuum break.Heat: recording from heat on to heat off.

Run\Sp: recording from HC900 Run to HC900 Stop.Segmt: recording only segments that have event 9 used in the Set Point Profile program.

6.5 WORK T/C S ELECT Select Screen 6 Page 3 1-4 End Point T/C Select or Screen 6 Page 4 5-8 End Point T/C Select orScreen 6 Page 5 9-12 End Point T/C Select

Any combination of work Thermocouples can be assigned as an endpoint to be used in conjunction with theHoneywell HC900 set point profile event 6 Hold for Endpoint Controller before allowing the program tocontinue to the next segment witch is typically the heat off cool down segments.

The Work T/C Select has four settings:

6.5.1 AutomaticIf a working thermocouple is present, this setting will use the T/C as an active endpoint.

The temperature designated in the Recipe Profile will have to be achieved before process will continue. If the T/C fails it will be disregarded and the minimum number of T/Cs to be achieved will be automatically reduced.

6.5.2 InIf a working thermocouple is present, this setting will use the T/C as an active endpoint.

The temperature designated in the Recipe Profile will have to be achieved before process will continue. If the T/C fails the Non-Critical Alarm will trigger.

6.5.3 Out This Setting will ignore any T/C regardless of Condition. This Setting is useful when a T/C looses contact with the work piece or it becomes unstable. If the T/C fails noalarm will trigger.

6.5.4 SurveyIf a working thermocouple is present this setting will use the T/C as a Survey only.

The T/C will not be designated as an active endpoint controller, and the Recipe Profile Temperature will nothave to be achieved.

This setting is useful if there is a large deviation compared to the other work T/Cs.Example; if The Thermocouple is Selected to either In or Automatic and was placed too close to the workfixture resulting in a much colder reading that would cause the part to become overheated before the lagging

T/Cs Temperature would be achieved. Switching to the survey setting would only monitor the temperature.If the T/C fails the No Alarm will trigger.


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7. HONEYWELL USER UTILITY

This Section covers how the Honeywell Hybrid Control Utilities Pertains to the PV/T Vacuum BrazingFurnace.Refer to the Honeywell User Utility Manual for General Operation of the Program.

Using the Honeywell User Utility to set up the process is less time consuming then programming through theoperator interface.

The Honeywell HC900 User Utility will create or edit the programs used to control the process. These programs can be created on the PC and transferred to the HoneywellHC900 on floppy disk or uploaded through the RS-232 Serial or Ethernet Communication ports.Refer to the Honeywell HC900 Operations Manual for RS-232 Serial or Ethernet Communication ports.

The programs needed are:RecipeData Storage SettingsSet Point Profile

Create the Programs using this guide and Download to the HC900(Refer to the HC900 Operations Manual)

7.1 LOADING THE CONTROLLER FILE The Controller file needs to be loaded into the utility first. This file is provided by PV/T or can be stored to disk from the Honeywell HC900.

(Refer to the HC900 Operations Manual)

From the Main Menu Load the Controller file into the utility.File Open and select the .cde file

This file is provided by PV/T or can be stored to disk from the Honeywell HC900.(Refer to the HC900 Operations Manual)

Once the Controller file is loaded you can chose to create a new program or edit an existing one.


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7.2 RECIPE EDITOR

Select file, new, from the main menu of the Honeywell Hybrid Control Utilities and chose theRecipes tab. And select Recipe (Variables) Then ok to create a new Recipe file.

Honeywell User Utility Choose a New File Type Screen

To assemble a recipe add Variable Tags to the Recipe Items and enter the Analog value for each item in theVariable tag list

The Recipe Items to be defined are:

DPREADY (Diffusion Pump Ready) The Diffusion Pumps Normal operating (Temperature after one hour of operation) less 10F

DPCOOL (Diffusion Pump Cool) The temperature of the Diffusion Pump after reaching normal operating temperature and then turned off for 48minuets. Indicating that the backing pump and DP cooling water is are no longer needed.

DPALARM (Diffusion Pump Alarm) The Diffusion Pumps Normal operating Temperature plus 30F

ODTEMP (Open Door Temperature) The Temperature of the furnace that the Vacuum break is permitted to open enabling the Chamber door is toopen.

ENDTEMP (End Point Temperature) The Temperature for each work Thermocouple that would indicate the parts braze point.Each endpoint value could be a different temperature.


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Using the Select a Reference Configuration select the configuration program that was loaded from the fileopen menu.

Give the Recipe a name using 8 character DOS format and a Description.

To assemble a recipe add Variable Tags to the Recipe Items and enter the Analog value for each Item in therecipe Items list.

When all fields are entered save the file to a disk or if connected to the HC900 download directly to thecontroller when prompted give the recipe a name.


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7.3 P ROGRAMMING S ETPOINT P ROFILE FOR THE HC900

Select file, new, from the main menu of the Honeywell Hybrid Control Utilities and chose theRecipes tab. And select Set Point Profile Then ok to create a new Set Point Profile file.

7.3.1 Enter Profile Segments

For each segment Define:Segment type: ramp or soakGaur. Hold: Select off or onSP Value: (Temperature Deg. F)

Time/Rate: (time in Minutes)Events: Reference section 7.5Disregard Aux. out Value

Profile Editor Screen:


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7.3.2 Properties

Click on Properties to enter the Label and additional settings. Text Tab:Enter a Label Name for the Setpoint profile. This can be up to 8 characters.

Enter a Description for the Setpoint profile. This can be up to 16 characters.Enter a Primary Out Label for the Setpoint profile. This can be up to 8 characters.Enter Eng Units as F

Disregard the aux out label and aux out units.

Set Point Profile Properties Screen Text Tab shown:


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General Tab:Ramp Type: TimeGuar. Hold Type: Per Segment

Time Units: MinutesGuar. Hold High: Upper tolerance for guaranteed soaks in degrees Fahrenheit.Guar. Hold Low: Lower tolerance for guaranteed soaks in degrees Fahrenheit.

Set Point Profile Properties Screen General tab shown:

When all entries are completed save as file or download using the RS232 or Ethernet connection when allsegments are completed.


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7.3.3 Sample Program

SegmentG

Soak Time

(Minutes) Type Temp

F Events Notes

1 0.1 soak 0 1 Heat on2 20 ramp 67 Ramp @ 1600/Hr. to 600 in 20 min.3 on 10 soak 600 Soak at 6004 15 ramp 600 Ramp @ 1200/Hr. to 900 in 15 min.5 on 10 soak 900 Soak at 9006 10 ramp 900 Ramp @ 1200/Hr. to 1100 in 10 min.7 on 10 soak 1100 Soak at 11008 10 ramp 1100 Ramp @ 600/Hr. to 1200 in 10 min. Braze Temp9 0.1 soak 1200 7 Hold for High Vacuum

10 on 5 soak 1200 Soak at 1200 Braze Temp11 0.1 soak 1200 5 Hold for Endpoint Controllers12 0.1 soak 700 1 Heat off 13 on 0.1 soak 700 Cool Down14 0.1 soak 0 End Cycle


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Data Storage Editor Screen


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7.4.1 Analog Signals for trending.

Add signals to be recorded to the selected Tag list.

Signal Tag Name Unit

ScaleLow

ScaleHigh

WORK #1 Work #1 Thermocouple Degrees F 0 1300WORK #2 Work #2 Thermocouple Degrees F 0 1300WORK #3 Work #3 Thermocouple Degrees F 0 1300WORK #4 Work #4 Thermocouple Degrees F 0 1300WORK #5 Work #5 Thermocouple Degrees F 0 1300WORK #6 Work #6 Thermocouple Degrees F 0 1300WORK #7 Work #7 Thermocouple Degrees F 0 1300WORK #8 Work #8 Thermocouple Degrees F 0 1300WORK #9 Work #9 Thermocouple Degrees F 0 1300WORK #10 Work #10 Thermocouple Degrees F 0 1300WORK #11 Work #11 Thermocouple Degrees F 0 1300

WORK #12 Work #12 Thermocouple Degrees F 0 1300 TOPSIDES Top Side Zones Degrees F 0 1300BOTSIDES Bottom Side Zones Degrees F 0 1300

TOP Top Zone Degrees F 0 1300BOTTOM Bottom Zone Degrees F 0 1300REAR Rear Zone Degrees F 0 1300FRONT Front Door Zone Degrees F 0 1300DP TEMP Diffusion Pump Temperature Degrees F 0 1300FURNACE Furnace Temperature Degrees F 0 1300SETPOINT Process Setpoint Degrees F 0 1300WORK MIN Work Thermocouple Minimum Degrees F 0 1300WORK AVE Work Thermocouple Average Degrees F 0 1300

WORK MAX Work Thermocouple Maximum Degrees F 0 1300MICRONS Chamber Vacuum Thermocouple Microns 0 1000CCGAUGE Cold Cathode Gauge 1x10 -3 to 1x10 -8 Torr 0 10CAPMANOM Capacitance Manometer Torr 0 1000X10-4 Cold Cathode Gauge 1x10 -3 to 1x10 -4 Torr 0 10X10-5 Cold Cathode Gauge 1x10 -4 to 1x10 -5 Torr 0 10X10-6 Cold Cathode Gauge 1x10 -5 to 1x10 -6 Torr 0 10

When all entries are completed save as file or download using the RS232 or Ethernet connection when allsegments are completed.


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7.5 HC900 EVENTS

7.5.1 Event 1, Heat on\off This Event Toggles the heat on\off.

7.5.2 Event 2, Inert Gas on\off This Event Toggles the Optional Inert Gas on/off.Refer to the Inert gas section 11 of this manual for operation of the Inert gas.

7.5.3 Event 3, Forced Cooling on\off This Event Toggles the Optional Forced Gas Cooling on/off.

7.5.4 Event 4, Autotune This Event will turn on the Auto tune circuit and write new PID settings to the HC900 controller. Use this eventonly during a soak segment above 900F for a minimum duration of 10 minutes. Reference the Autotuneprocess section 9 for operation of the Autotune process.

7.5.5 Event 5, Hold for Endpoint Controller This Event will place the HC900 Program in a Hold State that will be released only when the combination of minimum number work Thermocouples have achieved their pre-designated Temperature contained within theProfile Recipe.Refer to the Endpoint Controller Section 6.3.1 of the Operations Manual.

7.5.6 Event 6, User Hold This Event Places the Program on hold for Operator intervention. This event is useful for any manual operation during the process such as a manual gas purge.When the operation is completed the operator places the HC-900 back into Run.

7.5.7 Event 7, Hold for Vacuum 1VGSP3 This Event will place the HC900 Program in a Hold State that will be released only when RelaySetpoint #3 of the MM200 Vacuum Gauge has been achieved.

This Setting is Factory Set at 9x10 -5 Torr and it is user configurable.Refer to the MM200 Vacuum Gauge Section 18.2 of the Operations Manual and the Televac MM200Operations Manual for Settings adjustment.

7.5.8 Event 8, Hold for Vacuum 1VGSP4 This Event will place the HC900 Program in a Hold State that will be released only when RelaySetpoint #4 of the MM200 Vacuum Gauge has been achieved.

This Setting is Factory Set at 600 Torr and it is user configurable. This setpoint is controlled by the Capacitance manometer and is shared with the inert gas process. Thesetpoint can be used to control the inert gas pressure or a process hold for vacuum level.Refer to the MM200 Vacuum Gauge Section 18.2 of this Manual and the Televac MM200 Operations Manual

for Settings adjustment.

7.5.9 Event 9, Record SegmentWhen this Event is selected it will start the recording of the trending. This segment is intended to record onlyparticular segments of the cycle. This function works with the Trend Selector (Screen 4 Page 2)Select Trending to Batch and Batch Trend to Segmt


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8. S WITCHING FROM PID OPERATION TO M ANUAL If necessary you can switch any zone from automatic operation to control manually.Once the zone is switched to manual you can override the automatic settings and enter a user value for theprocess set point or the percentage output for an individual zone.

Select screen 2

Use the page up or page down to navigate to Page 2 the Multi-loop faceplate.

Use the Tab key to select the zone to be adjusted.

Switch the zone from Auto to Manual.

Press the detail key, once to change the set point (SP) Press the key again to change thepercentage output.

Use the numeric keys to enter a new SP temperature below 1300F or enter a percentage 0-100for the OUT.

When enter is keyed the new settings will be stored. Tease settings will remainuntil another manual setting is selected or the zone is placed back into the automode.


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9. A UTO TUNING

Autotune will automatically tune all the PID loops for all zones simultaneously.Caution: Once the autotune is initiated it can not be canceled.

You can Autotune the furnace by running the autotune setpoint profile program or during any heat cycle.

Setpoint Profile Program #98Running this program will ramp and hold the furnace at 900F. Then the autotune will start by the use of event#10. When the cycle completes the furnace PID loops will be tuned.

During a cycle: Place the Honeywell HC900 in hold at any temperature above 900F. Use the control utility toturn on the autotune. Once autotune has completed place the process to RUN again.

The progress of the autotune can be observed on screen 1 Page 4 ZONES AUTOTUNNING they willindicate TUNING and change to TUNED when the zone has completed autotune.

10. B AKEOUT

A furnace bake out is periodically necessary when there is a noticeable decrease in vacuum performance. The Bake out process will boil off impurities accumulated on the furnace interior surface.

Place the furnace in high vacuum and ramp and hold the furnace temperature at 1200F. Raise thethermostatic control for the furnace jacket temperature to 180F. Maintain the water jacket temperature at180F for a minimum of 6 hours. This should be sufficient time for a proper bake out.

The Honeywell Setpoint Profile Program #99 is a Bake out program. Running this program will ramp and soakthe furnace at 1200F for 6 hours. Raise the Thermostatic control for the furnace jacket temperature to 180F

11. INERT G AS OPERATION

Inert gas is used to purge undesirable gases in the furnace. This operation can be preformed manually by the inert gas pushbutton on the graphic panel or automaticallyby using event 2 in the HC900 setpoint profile program.Proceed as follows:Evacuate Chamber to a high vacuum level then close off the pumping valves.Flood the chamber with inert gas. (Chamber will fill to the pressure setpoint #4 on the Televac MM200)Re-evacuate the chamber to a high vacuum level; this process can be preformed multiple times if desired.


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12. CONTROL UTILITY

The Control utility is used to manually interact with the automatic process.

Send End Signal: The Send End signal works the same as if all the end point temperatures have achievedtemperature.

Reset End Points: The reset end points is used if the end points have all achieved temperature and then theprocess is interrupted and has to be resumed at a earlier segment. Manually resetting the end point controlleris unnecessary at the end or the beginning of a cycle because they are automatically reset at those points.

Auto Tune: This will automatically set the PID settings for all heating zones.Caution: Once the autotune is initiated it can only be canceled by a cold restart of the HC900 controller.

Heat on\off: When running the system in the auto mode the heat control on the graphic panel is locked out. Inorder to manually control the heat during the automatic cycle is to set the heat control to manual in the setupoptions and then you will be able to toggle the heat on\off from the control utility.


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13. S HUT DOWN

Whenever the furnace is not to be used for some prolonged period of time, or if maintenance is to be done thesystem should be shut down.

13.1 AUTOMATIC

To shut down the system automatically, first put the mode switch in the AUTOMATIC position, close thefurnace chamber doors, and then depress the push button marked SHUT DOWN. Upon doing so theDiffusion pumps will shut off and the AUTO PUMP OFF pilot lamp will come on. If the furnace pressure isabove cross over, the Rough Valves will open to evacuate the chamber. Once the cross over vacuum level isreached, the Rough Valves will close and the Blowers and Rough Pumps will shut off. After the Diffusionpumps has had time to cool, the Hold Pump Valves will close and the Hold pumps will shut off. Once this isdone, the control and instrument power may be turned off by pressing the E-STOP button.

13.2 MANUAL

If it is desired to shut the system down manually proceed as follows:

1. Put the mode switch in the MANUAL position.2. Turn off the Diffusion Pumps by pressing their push buttons.3. Open the Hold Pump Valves to maintain vacuum in the Diffusion Pumps while cooling.4. Open the Rough Valves with its push buttons to evacuate the furnace chamber.5. When the chamber's vacuum level reaches the micron range, close the Rough Valves.6. Turn off the Rough Pumps by depressing their push buttons.7. After the Diffusion Pumps have had time to cool, close the Hold Pump Valves.8. Shut off the Hold Pump.9. Press E-STOP to turn off the control and instrument power.


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14. A LARMS

Incorporated into the system are several independent alarm mechanisms designed to protect the furnacesystem and the workload. They are as follows:

Critical Alarms are as follows:Failure of PumpsLoss of powerFailure of the vacuum valves to open or closeLoss of compressed airVacuumLoss of cooling waterFurnace is over heatedFurnace Zone is over heatedDiffusion Pump is over heatedController HardwareSystem ThermocouplesCMOS Battery

In the event that any of these alarms are triggered, the alarm bell will sound the HC900 will go into Hold, andthe illuminated beacon will flash. The system will take appropriate action, dependent on the nature of thealarm, to preserve the integrity of the system and/or the workload. Once the alarm bell has the operatorsattention the bell can be silenced by pressing the Alarm silence pushbutton. The illuminated beacon willcontinue to flash as long as the alarm condition still exists or goes unacknowledged. If any alarm is notacknowledged within fifteen minutes the system will automatically shut down. Once the problem has beenrectified, the alarm conditions will self clear.

Non Critical Alarms:Loss of Work Thermocouples

A non critical alarm will not interrupt the process. And is distinguishable from a critical alarm by theintermittent alarm bell.

14.1 ALARM OVERVIEW When an alarm occurs the type of alarm can be identified by viewing the Alarm Overview screen 5 Page 1on the Honeywell HC900. Details on Thermocouple alarms can be viewed by paging through the alarmscreens. When the alarm is identified the operator must acknowledge the alarm by pressing the AlarmAcknowledge Pushbutton. The alarm silence pushbutton does not acknowledge the alarm it only silences thealarm bell.


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14.2 CRITICAL ALARMS

Critical Alarms require immediate attention. If the cause of a Critical Alarms is determined and quicklycorrected the process cycle could be resumed.

The Critical Alarms are:

14.2.1 Pumps This Alarm indicates that a pump has dropped out or did not start.

Rough Pump:Should the mechanical roughing pump motor starter drop out due to overload, the Rough and Foreline valveswill close, and the ROUGH PUMP pilot lamp will flash. If the Hold pump is also off, the Diffusion pump will beshut off. To reset the alarm the main power must be shut off, the control cabinet must be opened, and themotor starter must be reset.

Blower:Should the Vacuum Blower motors starter drop out due to overload, the BLOWER pilot lamp will flash. Toreset the alarm the main power must be shut off, the control cabinet must be opened, and the motor startermust be reset.

Hold Pump:Should the mechanical holding pump motor starters drop out due to overload, the Hold Pump Valve will close,and the HOLD PUMP pilot lamp will flash. If the Rough pump is also off, the Diffusion pump will be shut off.

To reset the alarm the main power must be shut off, the control cabinet must be opened, and the motorstarter must be reset.

Diffusion Pump:Should power to the Diffusion pump be lost, the High Vacuum valve will close, and the DIFFUSION PUMP

pilot lamp will flash. When this occurs check if the HC900 indicates a Diffusion pump over temperaturecondition, if not check the Diffusion pump Circuit breaker or the two bi-metal temperature switches on thebody of the diffusion pump that might need to be reset.

Water Recirculation Pump:Should the water recirculation pump motor starter drop out due to overload, the furnace heat will shut downand the WATER PUMP pilot lamp will flash. To reset the alarm the main power must be shut off, the controlcabinet must be opened, and the motor starter must be reset.

14.2.2 Power There are three different alarms associated with power. In all cases the problem will be a tripped circuitbreaker located within the control panel. They are:

1. Loss of power to the PLC input modules.2. Loss of power to the PLC output modules.3. Loss of power to the PLC pilot lamp modules.

To reset the alarm the main power must be shut off, the control cabinet must be opened, the cause of thecircuit breaker overload needs to be identified and corrected.


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14.2.3 ValvesVacuum Valves not Open or Closed:If any of the vacuum valves (Rough, Foreline, High Vac, or Vacuum Break) cannot open or close within a timelimit the ALARM pilot lamp will flash along with the pilot lamp of the valve in question. If the Foreline or HighVac fails to close properly the Diffusion Pump will be shut off.

14.2.4 AirIndicates the compressed air supplying the pneumatic valves has dropped below 60 PSI.

The compressed air supply is required to operate the various pneumatic valves and cylinders in the system. This air supply must be at a minimum pressure of 60 psig as measured by the air pressure switch. Shouldthe pressure drop below 60 psig the air alarm will be triggered and the ALARM pilot lamp will flash. Also allopen pneumatic valves will close. Upon the return of air pressure, the valves will resume their previousstatus, and the alarm will have to be acknowledged.

14.2.5 Vacuum There are five different conditions which will cause a VACUUM ALARM.

Foreline Time to Pressure:Whenever pumping down from above 5 Torr, the foreline pressure must reach 5 Torr in less than two minutesif the Foreline Valve is open, or twenty minutes if only the Hold Pump Valve is open. If either of theseconditions cannot be met the diffusion pump will not be turned on. This alarm is disabled if the system is inthe Maintenance Manual mode.

Foreline Rise in Pressure:After the foreline has been pumped below 5 Torr and if the diffusion pump is hot, the pressure must not riseabove 5 Torr. If this alarm is triggered the diffusion pump will be shut off.

Chamber Time to Cross Over:Starting from the opening of the Rough Valve, the chamber must reach the cross over vacuum level on the

TC portion of the vacuum gauge in ten minutes or less. This alarm is disabled when the system is in theMaintenance Manual mode.

Chamber Time to High Vacuum:Once the high vacuum valve opens the chamber must reach high vacuum, as determined by relay on the coldcathode portion of the vacuum gauge, in less than two hours. If this vacuum level cannot be reached, thecycle will be halted until the alarm is reset. This alarm is disabled it the system is in the Unsafetied Manualmode.

Chamber Rise in Pressure:If after reaching high vacuum, the chamber pressure rises to 50 microns while the High Vacuum valve isopen, the alarm will come on and latch. If the pressure continues to rise to 100 microns, the High Vacuumvalve will close. To reset the alarm the furnace must be in high vacuum, or the mode switched to Manual.


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14.2.12 BatteryHC900 CMOS Battery Low:If the battery is found to be low in the process controller as indicated by a continuous alarm bell and the Alarmoverview screen (screen 5 Page 1 on the Honeywell HC900) the system will have to be shut off and the

battery will have to be replaced per the Installation & Operation Manual for the Honeywell HC900.

14.3 NON-CRITICAL ALARMS

Non-Critical Alarms are identified by an intermittent alarm bell. This non-critical alarm will not disturb theprocess in anyway it is for informational purposes only.Once a non-critical occurs the operator needs to acknowledge it.

14.3.1 Work T/C FailureWhen there is a Work Thermocouple failure as indicated by an intermittent alarm bell and is displayed on

screen 5 page 3 Work T/C Alarms on the Honeywell HC900.Note: When a work T/C is set to Auto or Out as selected in the End Point T/C Select no Alarm will occur.Refer to the HC900 Setup Section 6.5 Work T/C Select.


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15. P UMP & V ALVE INTERLOCKS

The system is interlocked by various means to help avoid improper operation. Some of theseinterlocks can be overridden by entering the Unsafe Manual mode as indicated by an *. Theinterlocks are as follows:

15.1 ROUGH P UMP

For the rough pumps to be on the following must be true:

The control system is enabled and all power is on.An alarm for rough pump off is not in progress.Water for the pump is OK.

15.2 VACUUM BLOWER

For the vacuum blower to be on the following must be true:

The rough pumps are on. The foreline or the rough valve needs to be openAn alarm for vacuum blower off is not in progress.

15.3 ROUGH P UMP VACUUM BREAK VALVE

For the rough pump vacuum break valve to be open the following must be true:

The rough pump is off. The rough valve is closed. The foreline valve is closed.

15.4 HOLD P UMP

For the hold pump to be on the following must be true:

The system is enabled and all power is on.An alarm for hold pump off is not in progress.

15.5 HOLD P UMP VACUUM BREAK VALVE

For the hold pump vacuum break valve to be open the following must be true:

The hold pump is off. The hold pump valve is closed.


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15.6 HOLD P UMP VALVE

For this valve to be open the following must be true:

The hold pump is on. The air supply for pneumatics is above 60 PSIG.

15.7 DIFFUSION P UMP

For the diffusion pump to be on the following must be true:

The rough pump or the hold pump is on.Foreline pressure has been below 100 microns.Foreline pressure remains below 500 microns.

It is not over temperature.Water for the pump is OK.Alarm for foreline valve not closed is off.Alarm for high vacuum valve not closed is off.Alarms for foreline vacuum are not in progress.

15.8 ROUGH VALVE

For this valve to open all of the following must be true:

The rough pump is on. The air supply for pneumatics is above 60 PSIG. The chamber door/doors are closed. The foreline valve is closed. The high vacuum valve is closed. The vacuum break valve is closed.In an automatic cycle the following also must be true:

The chamber pressure is above 100 microns.Alarm for foreline vacuum is off.

15.9 FORELINE VALVE


The rough pumps are on. The air supply for pneumatics is above 60 PSIG. The rough valve is closed.

In an automatic cycle the following also must be true: The chamber pressure is below 100microns.


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15.10 HIGH VACUUM VALVE


The chamber pressure is below 100 microns. The air supply for pneumatics is above 60 PSIG. The chamber doors are closed. The rough valve is closed. The vacuum break valve is closed.

In an automatic cycle the following also must be true:

The foreline valve is open.Alarm for foreline vacuum must be off.

15.11 VACUUM BREAK VALVE


The air supply for pneumatics is above 60 PSIG. The chamber door\doors are closed. The rough valve is closed. The high vacuum valve is closed.

15.12 HEAT

For the heat to be on all of the following must be true:

The furnace water supply is on. The VRT water supply is on. The chamber door\doors are closed. The HC900 is functioning. The over temperature controller is reset.No zone controllers are in alarm.No VRTs are over temperature.


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16. P RECAUTIONS

The furnace should never be operated without all services being connected and on.Be sure the mechanical vacuum pumps rotation is correct per the pump owner's manuals.

The furnace should be left under vacuum when not in use.Be sure that a supply of inert gas is connected to the proper inlet coupling, and that the gas lineshave been purged. Failure to do so could result in unwanted oxidation of the product.All materials placed in the furnace should be carefully checked for vapor pressure at maximumoperating temperature. Failure to do so could result in the severe contamination of the system.All materials placed in the furnace should be thoroughly de-greased and cleaned.

The rough valve and the foreline valve should never be open at the same time.


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17. TROUBLE S HOOTING AND M AINTENANCE

All maintenance and service procedures should be followed per the supplementary instructionssupplied with this manual.

Caution! Do not service alone

Caution! This equipment has high voltage supplied from multiple sources.Disconnect all service connections and lockout disconnects before servicingequipment.

A program of regular inspection and maintenance of the vacuum furnace is essential to the safeand continuous operation of the equipment and should be instituted and followed rigorously.

17.1 VACUUM S YSTEM

17.1.1 General

Numerous stationary and moving vacuum seals, O-rings and other rubber gaskets are associatedwith the main vacuum vessel. These seals should be inspected regularly to ensure cleanliness,

freedom from cracks or gouges, and retaining elasticity. The main door where work regularlypasses should receive particular attention.

The vacuum chamber and all associated plumbing should be kept clean and free of contamination. If cleaning is required it should be done with a lint free cloth dampened with asolvent consistent with the contaminant. Acetone or alcohol should be used for final cleaning. If the contamination is severe the vacuum piping and valves should be dismantled and cleanedseparately.

The condition and level of oil in the mechanical vacuum pumps and the diffusion pump is criticalfor their proper operation. Since the effect of the users process on the oil is unknown at thiswriting, the condition and level of the pump oil should be checked after every cycle until therequired frequency of oil change is determined.


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17.1.2 Mechanical Pumps check List

Mechanical vacuum pumps should be checked and repaired as required.A partial check list follows:

Drive belts are not worn

Drive belts have the proper tensionNo oil leaks at the shaft sealsCorrect oil levelOil is free of dirt and water accumulationDrip legs are drainedMounting bolts are tightVacuum lines and vibration couplings are tightCorrect water flow for cooling

17.1.3 Diffusion pump check list

Diffusion pumps should be checked and repaired as required. A partial check list follows:

Correct water flow for coolingHeating elements are tight and indicate proper electrical parameters.Correct oil levelOil is not contaminated

17.1.4 Vacuum valves check list

Vacuum valves should be checked and repaired as required.A partial check list follows:

Air supply filter is drained and operating.Air supply oilier is filled to the correct level and is operating.Pilot valves are not leaking excess air.Moving O-ring seals cleaned or changed where indicating excess wear.

17.2 P OWER S UPPLY

The furnace power supply should be inspected and corrected as required.A partial check list follows:

Primary and secondary wiring and cables tight and free from overheatingProper ventilation and air cooling or proper water flow.Relays and contactors should be free of contact pitting which could result in arcing that couldcause contact welding.Power supply voltage and current should be monitored to ensure that design limits are notexceeded.


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17.3 S ENSORS

The condition of the various pressure, vacuum, and temperature sensors is critical for the safeand consistent operation of the system.

17.3.1 Thermocouples

A regular replacement program should be established for all thermocouples.

Note: The effective life of thermocouples varies depending on their type, the process, andtemperature and vacuum levels. These factors must be considered in setting up a replacementschedule.

17.3.2 Vacuum Gauge Tubes

A regular replacement program should be established for all vacuum gauge tubes.Note: The effective life of gauge tubes varies depending on their type and the process. Thesefactors must be considered in setting up a replacement schedule.

17.4 INSTRUMENTATION

All the various instrumentation for temperature, vacuum, etc., should be set up on a regular testand calibration schedule.

Batteries for retaining RAM memory in such devices as programmable logic controllers, messagecenters, operator interface terminals, etc., should be tested and replaced on a regular schedule.Check the battery indicator on the front of your Allan Bradley SLC 5/01 PLC processor and theinstallation date written on the battery cover and change promptly if needed.

17.5 P ILOT LAMP T EST

Pressing the alarm silence pushbutton will illuminate all the pilot lamps. The alarm silencepushbutton can be used at any time to test the pilot lamps on the control panel.

17.6 INTERLOCKS AND ALARMS

Periodic checks of all safety interlocks and alarms should be performed. Particular attentionshould be given to over temperature safety devices, low air pressure, insufficient cooling water,vacuum, oil temperature, and low oil alarms (as applicable to the system).

17.7 COOLING

Many components of the vacuum furnace require water cooling. Drain lines should be inspectedfor proper flow and temperature of the cooling water. Pressure regulators, strainers, and safetyvents should be inspected for proper setting and be maintained free from dirt and contamination.

If an evaporative cooling tower is integral to the furnace system, the tower should be cleaned, themotor and bearings greased, and the water strainers cleaned on a regular basis.


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17.12 P ERIODIC MAINTENANCE CHECK LIST

Note: Frequency of maintenance of the following will depend on furnace use and therecommendation of the individual equipment manufacturers.

Inspect vacuum chamber O-rings and other gaskets for proper sealing.Check the vacuum chamber vessel for evidence of hot spots indication of improper water cooling.Examine furnace internals in detail for heating element, heat shield, work support, or mechanismdeterioration or failure.Lubricate motors, drives, valves, blowers, compressors, pumps, etc., as required.With brush or other device remove major build up of oxides and contamination from the hot zoneand accessible areas of the cold wall chamber. Blow out contamination with dry air.Run furnace to near maximum design temperature and maximum vacuum to boil out furnacecontamination.Install new valve springs and discs and clean and flush oil from the mechanical vacuum pumps.Replace spring and O-ring in the gas ballast valves (see pump instructions).Run blank off test for the mechanical vacuum pumps to ensure meeting process parameters.


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18.2 T ELEVAC MODEL MM200

For procedures on modifying the station assignments and four relay setpoints on the vacuumgauge refer to section 500 in the Televac model MM200 instruction and service manual.

The setpoints should be configured as follows:

Televac MM200 setpoints:

SP# CH# ON OFF COMMENTS1 1 (2A) 100 microns 110 microns Crossover2 2 (2A) 100 microns 500 microns Foreline3 7 (CC) 9 x 10 -5 Torr 2 x 10 -4 Torr Process4 5 (5A) 600 Torr 740 Torr Inert Gas

Note: Setpoint #3 is dependant on the workload and should be selected accordingly.

Red illuminated numbers on the Televac MM200 indicate that a setpoint has been achieved.

vacuum aluminum brazing furnace

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