E Copyright by UNIFLAIR, 1996 vers. 1.6 - - 24.06.96

UNIFLAIR

MICROPROCESSOR CONTROL

mP3

INSTRUCTION MANUAL

Study this manual carefully before using the controlsystem and keep it in a safe place for future reference.

N.B.: No part of this publication may be reproduced, stored in a retrievalsystem or transmitted in any form or by any means, electronic,mechanical or otherwise without the prior permission ofUNIFLAIR.

1vers. 1.6 - - 24.06.96

2 vers. 1.6 - - 24.06.96

INDEX

PRECAUTIONS page 3. . . . . . . . . . . . . . . . . . . . . . . . . . .START- -UP REMINDER page 3. . . . . . . . . . . . . . . . . . .STOPPING THE UNIT page 3. . . . . . . . . . . . . . . . . . . . .CONTROL PANEL REPLACEMENT page 3. . . . . . . .CHARACTERISTICS OF THE SYSTEM page 5. . . . . .POSITION AND FUNCTIONOF THE CONTROLS page 5. . . . . . . . . . . . . . . . . . . . . .

Keypad page 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .LED indicators page 5. . . . . . . . . . . . . . . . . . . . . .Liquid Crystal Display page 5. . . . . . . . . . . . . . . .Audible Alarm page 5. . . . . . . . . . . . . . . . . . . . . . .

REAR page 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .INTERNAL page 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Configuration DIP switches page 7. . . . . . . . . . . .Offset trimmer page 7. . . . . . . . . . . . . . . . . . . . . .Sensitivity trimmer page 7. . . . . . . . . . . . . . . . . . .Input connector page 7. . . . . . . . . . . . . . . . . . . . . .Output connector page 7. . . . . . . . . . . . . . . . . . . .Supply and alarm connector page 7. . . . . . . . . . . .Serial line connector page 7. . . . . . . . . . . . . . . . . .

SERIAL LINE INTERFACE ADAPTOR(ASM2) page 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ADDITIONAL ALARM CARD page 8. . . . . . . . . . . . . .INSTALLATION AND CONFIGURATION page 9. . . .

Hardware configuration page 9. . . . . . . . . . . . . . .Software configuration page10. . . . . . . . . . . . . . . .Initial checks page11. . . . . . . . . . . . . . . . . . . . . . . .Control Start Up. page11. . . . . . . . . . . . . . . . . . . .

ADJUSTMENTS AND SETTINGS page11. . . . . . . . . . .Adjustment of the sensor page11. . . . . . . . . . . . . .Adjustment of air flow sensor page11. . . . . . . . . . .Range of factory settings page12. . . . . . . . . . . . . .Range of temperature setpoint page12. . . . . . . . . .

UNIT START- -UP page13. . . . . . . . . . . . . . . . . . . . . . . . .CONTROL ALGORITHMS page13. . . . . . . . . . . . . . . . .CONTROL DIAGRAMS page15. . . . . . . . . . . . . . . . . . .

Notes on the control diagrams forthe return air temperature page15. . . . . . . . . . . . .A- -Direct Expansion Versions page15. . . . . . . . . .B- -Chilled Water Versions page16. . . . . . . . . . . . .Dehumidification page16. . . . . . . . . . . . . . . . . . . .

ALARMS page17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .FAULT FINDING page19. . . . . . . . . . . . . . . . . . . . . . . . .

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PRECAUTIONSD Connection and disconnection of the control panel mustonly be carried out when the power supply to the airconditioning unit has been cut (main isolator of theelectrical compartment to off). Push the respectiveconnectors into their sockets and ensure that they arecorrectly located: do not force them if they are difficult topush home.

D Under no circumstances bridge the contacts of the flowsensor; this could damage the PCB.

D Since the program reads the keypad at intervals of a fewtenths of a second, it can happen that the push of a keymay be ignored if pressure was not applied for longenough. In this case simply exerting greater pressure onthe key is useless and could even cause damage. It issufficient to simply press the key for longer until thesystem responds.

D TRANSPORT: if it should be necessary to move the airconditioning unit to a new location (even from one roomto the next) it is advisable to remove the control panelfrom the unit and pack it separately, preferably in itsoriginal container.

START UP REMINDER

D Connect the power supply to the electrical panel of the airconditioner, close the main isolator on the unit and checkthat the yellow LINE LED is illuminated.

D Do not start up the unit for at least 24 hours (ie: do notpress ) if it is of the direct expansion type (ie: withcompressor(s) on board) in order to allow the crankcaseheater time to ensure that any refrigerant liquid in thecompressor crankcase has evaporated.

D 24 hours after activating the power supply, START theunit by pressing : this activates output 1 (control of thefan(s)), the green SYSTEM ON LED is illuminated andthe values of room temperature, temperature set- -pointand differential appear in the display (see page 11).

D In the event of an alarm, signalled by the built- -in sirenand the red ALARM LED, consult the ALARMS section(page 17).

STOPPING THE UNIT

D STOP the unit by pressing .D Only for long shutdown periods (more than one week)should the on- -board isolator be opened.

CONTROL PANEL REPLACEMENT

D If the control panel has to be replaced at any time, the newpanel must be configured for the unit in which it isinstalled, see: INSTALLATION ANDCONFIGURATION (page 9).

4 vers. 1.6 - - 24.06.96

~LINE

SYSTEM ON

COOLING

HEATING

ALARM

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

SET DIFF

C- -1

b

dc

b

a

C- -2 SET DIFF

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CHARACTERISTICS OF THE SYSTEM

The mP3 system which controls the dry bulb temperature byoperating the cooling and reheating facilities of the airconditioning unit, comprises a control card complete withthe interface devices (for the electrical connections forinput, output, and power supply) and an operating panel,assembled in a single box which forms the control panelitself.

The control card, the heart of the system, is fitted with themicroprocessor, a read- -only memory (the EPROM whichcontains the program), a read/write memory (a RAM, forthe operating variables) and a permanent read/writememory (the E2PROM, which maintains data in the eventof a power failure).

The control card is connected to the electrical panel with 3connectors, one 11- -way, one 7- -way, one 5- -way.

For room relative humidity control, the optional hP3controller can be connected to the mP3 system in order tooperate the humidification and the dehumidificationfunction (consult the appropriate manual).

By using a special adaptor supplied on request (ASM2),both systems can be connected to a data gathering system viaa serial line and the connector fitted on the rear of the panel.

mP3 microprocessor is immune from electromagneticinterferences according to IEC 801- -4 standard, level 3.

POSITION AND FUNCTION OF THE CONTROLS

KEYPAD

The key pad comprises 6 membrane keys identified bysymbols printed on the polycarbonate front panel cover(fig. C- -1).

Each key has one or more functions, depending upon thetype of menu against which the cursor is located, as follows:

Alarm mute button. Pressed once this key mutes theaudible alarm and de- -energizes the general remotealarm signal relay; pressed twice it causes the reset ofthe alarm status.

System on key. The status is memorized to permitintelligent automatic restart: on the return of power,the unit reverts to the status which it had before thepower was cut.

System off key. This key does not reset any alarmswhich may have occurred.

This key selects the value tobeadjusted (set point andproportional band). When pressed for about 5seconds it permits the setting of the minimum andmaximum ambient temperature limits.

Key to increase numerical input values (set point,band width, etc.). Holding this key depressed speedsup the rate of increase of the value.

Key to decrease numerical input values. This key hasthe same function as the above but in reverse.

LED INDICATORS

On the front panel (fig .C- -1) there are 5 LEDs each ofwhich indicates a different function:

- -~LINE: a yellow LED indicates power on;- -SYSTEM ON: a green LED indicates the on/off status ofthe unit;- -COOLING: a green LED for the outputs used forcooling;- -HEATING: a green LED for the outputs used for heating;- -ALARM: a red LED for alarm conditions in general.

LIQUID CRYSTAL DISPLAY

The following items are indicated on the liquid crystaldisplay (figs. C- -1 and C- -2) depending upon the operatingmode of the unit at the time:

Display of temperature; configuration or alarms;

Indicators of alarm situations;

Display of set values;

Display of the value of temperature control sensitivity.

AUDIBLE ALARM

a

b

c

d

6 vers. 1.6 - - 24.06.96

C- -3

A ON1

1 2 3 4 5 6 7 8 9 10 11

12 13 14 15 16 17 18 19 20 21 22 23

C- -4

B

C

C

1

pin 1 - - GND

pin 2 - - TX+

pin 3 - - TX- -

pin 4 - - RX+

pin 5 - - RX- -

C- -5

DL1ON

1

SW1

B

AC

234

RS422

ASM2

7vers. 1.6 - - 24.06.96

REAR

The rear of the control panel is covered by a protective panelleaving the lower portion open for connections.

Identification Label

An identification label is fixed in one of the positions Ashown in figure C- -3 and gives the identification details ofthe control:

- - name of manufacturer;- - date of manufacture;- - manufacturers serial number;- - manufacturers product code.

By pressing the two lateral indentations (C in fig. c- -3) therear protective panel B can be removed in order to gainaccess to the control board.

INTERNAL

Fig. C- -4 indicates the essential components of the board:

Configuration DIP switches(page 9);

Offset Trimmerfor adjusting the temperature sensor reading (page 11);

Sensitivity Trimmer of air flow sensor interventionthreshold (page 11);

Input connector

Ia - - TEMPERATURE SENSOR INPUT

The first input (between terminals 10 & 11) is dedicated tomonitoring the ambient temperature by reading an NTCtype passive thermistor sensor (negative temperaturecoefficient), with an accuracy of 0.5C.

Ib - - AIR FLOW SENSOR INPUT

The second input (terminals 8 and 9) is used to detect anadequate air flow; depending on the type of unit, it may be:

- -a PTC (Positive Temperature Coefficient) thermistor;- -a pressure differential switch with a contact, closing acrossa resistor of 330 4W on the specific input (terminals 8and 9).

II - - DIGITAL INPUTS

Each opto- -isolated input reads the status (open or closed)of the contact between it and the common (terminal 1). Thedata acquisition system is of the fail-safe type: the normalstatus is closed contact so that any faulty connections or badcontacts are immediately recognized as faults.

For this reason, all inputs which are not in use must bebridged with the common (terminal 1) except for thedehumidification input which, if closed, activates cooling forthe purpose of dehumidification.

There are 6 inputs available, connected as follows:

- - input 1 - - electric heater safety thermostat (terminal 2);- - input 2 - - clogged filter pressure switch (terminal 3);- - input 3 - - receipt of humidity control alarm status (fromhP3) and/or of optional alarm devices (water under floorsensor, ambient high/low temperature and humidityswitches, smoke/fire sensors) (terminal 4);

- - input 4 - - request for dehumidification (terminal 5)- - input 5 - - not used in CW units - - compressor lowpressure switch (in single compressor units) orcompressor alarm 2 coming from the additional alarmcard (in twin- -compressor units) (terminal 6).- - input 6 - - not used in CW units - - compressor highpressure switch (in single compressor units) orcompressor alarm 1 coming from the additional alarmcard (in twin- -compressor units) (terminal 7).

Output Connector

The digital outputs are achieved with live solid state relays(TRIAC) at 24 Vac.

Each output can provide a continuous supply up to 20 VA at24 Vac.

There are 5 outputs, connected as follows:

- -output 1 - - SYSTEM ON, fan operation (terminals 12and 15);- -output 2 - - HEATING, electric heating 1 contactor or, inconfiguration with heating valve, valve opening signal(terminals 13 and 15);- -output 3 - - HEATING, electric heating 2 contactor or, inconfiguration with heating valve, valve closing signal(terminals 14 and 15);- -output 4 - - COOLING, compressor 1 contactor (intwin- -compressor units), or only compressor contactor (insingle compressor units) or cooling valve closing signal (inCW units) (terminals 16 and 18)- -output 5 - - COOLING, compressor 2 contactor (intwin- -compressor units) or dehumidification relay (insingle compressor units) or cooling valve opening signal(in CW units) (terminals 17 and 18).

Supply and alarm connector

- - supply terminals (numbers 19 and 20);- -output 6 - - ALARM, general alarm output (relay withcontacts normally open between terminals 21 and 22 andnormally closed between terminals 22 and 23).

Serial line connector

For serial line connections, the interface adaptor ASM2must be used (see following paragraph).

8 vers. 1.6 - - 24.06.96

K1

D1

D2BA

C- -6

SERIAL LINE INTERFACE ADAPTOR

The main elements of ASM2 serial line interface adaptor areshown in fig. C- -5:- -Connector A to connect the ASM2 adaptor to mP3 andhP3 controls through the specific enclosed flat cable;- -9- -pin connector B wired as shown in the diagram, toconnect the ASM2 adaptor to the RS422 serial line;- -Selector SW1 with 4 DIP switches to set the serial address(from 1 to 15) with a binary code (1- -2- -4- -8 and therelevant combinations of the DIP switches);- -DL1 LED indicating the power supply (from mP3control).The connector C is not used in this application.The serial line may be used to connect the unit to a BuildingManagement System to get:- - remote start and stop of the unit;- - reading and set point adjustment of regulation and alarmparameters(room temperature set point and differential,high and low temperature and humidity limits, etc.);- -acquisition of the outputs status;- - reading of temperature and humidity (with hP3 control)measured by the sensor of the unit;- -acquisition of the alarm status.The transmission protocol is available on request.

ADDITIONAL ALARM CARDIn twin- -compressor units, the control system includes anadditional card (mounted in the electrical compartment ofthe unit) which monitors the compressor safety devices andgenerates a supplementary output for the control of thedehumidification valve.Figure C- -6 illustrates the principal components of the card:- - relay K1 for control of the dehumidification valve;- - trimmer D1 for adjusting the time delay of compressor 2low pressure switch;- - trimmer D2 for adjusting the time delay of compressor 1low pressure switch;- - two bridges A and B for selecting the dehumidificationcontrol output logic (in the position shown to control thesolenoid valve);- - terminals for the electrical connections.The card is equipped with 7 inputs connected as follows:- -between terminals C and 5 the normally open auxiliarycontact of compressor 2 (CC2);- -between terminals C and 6 the normally open auxiliarycontact of compressor 1 (CC1);- -between terminals 7 and GO the call for dehumidificationcoming from the hP3 humidity controller;- -between terminals 1 and GO the high pressure switch ofcompressor 2 (AP2);- -between terminals 2 and GO the low pressure switch ofcompressor 2 (BP2);- -between terminals 3 and GO the high pressure switch ofcompressor 1 (AP1);- -between terminals 4 and GO the low pressure switch ofcompressor 1 (BP1).The card is also equipped with 3 outputs connected asfollows:- -between terminals 1c and 1no the passing supply for thecontrol of the dehumidification solenoid valve;- -between terminals 8 and GO the signalling of compressor2 alarm to the mP3 controller;- -between terminals 9 and GO the signalling of compressor1 alarm to the mP3 controller.The 24 V a.c. supply to the card comes via the terminals Gand Go.

9vers. 1.6 - - 24.06.96

ON1

C- -7

INSTALLATION AND CONFIGURATION

Check that the power supply to the unit is off. Insert theconnectors in the appropriate sockets without forcing them.

At this juncture, the microprocessor control must beconfigured to suit the unit in which it is to be used.

Normally this operation is only required when the control isfirst installed in the unit and is therefore carried out in thefactory. However, it may sometimes be necessary at a laterstage if there have been any modifications to the unit or thesystem.

Configuration of the hardware is by means of dip switcheson the rear of the controller while a specific section of theprogram provides for software configuration via the keypad.

HARDWARE CONFIGURATION

For configuration of the hardware there are 4 dipswitches onthe rear of the controller (as shown in figure C- -7) whichprovide for the following selections:

dip N1 OFF ELECTRIC HEATINGdip N1 ON HEATING MODULATING VALVE

the choice between electric resistance heaters or a hotwater coil complete with 3 way modulating valve;

dip N2 OFF DIRECT EXPANSION UNITS(with compressor/s)

dip N2 ON CHILLED WATER UNITS(with modulating valve)

the choice between control of direct expansion units (withone or two compressors) or chilled water units (with 3 waymodulating valve):

dip N3 OFF CONTROL Pdip N3 ON CONTROL P + I

the choice between proportional or proportional +integral control;

dip N4 OFF DEGREES CELSIUSdip N4 ON DEGREES FAHRENHEIT

the choice between displaying values (actual figures,setpoints, differentials, etc.) in degrees Celsius orFahrenheit.

10 vers. 1.6 - - 24.06.96

S- -1

S- -2

S- -3

S- -4

S- -5

S- -6

SOFTWARE CONFIGURATIONTo obtain access to this section of the program, the mute keymust be depressed at the same time as power is applied

to the controller (ie:when the electrical panel is poweredup).The access code (password) is displayed in the bottom lefthand corner as shown in fig S- -1 and is keyed in usingand to arrive at the right digits and for acceptance.The access code is contained in the sealed envelope attachedto this manual and addressed to the maintenance manager,in order to prevent unauthorized access to the systemconfiguration.If the wrong code is entered access is denied. If the correctcode is entered the program will permit access and,depending upon the hardware configuration, the displayshows:

A. Direct expansion units (dip switch N2 OFF)- -INPUT N OF COMPRESSORS: fig. S- -2

This indicates the number of compressors, shown here as 1.

Using the or keys, the value can be modified from1 to 2 or vice- -versa. Depressing the key confirms theselection and displays the following choice, which dependson the number of compressors:- -LEAD/LAG COMPRESSOR CHANGEOVER(twin- -compressor units): fig S- -3A.S.C. (Automatic Switching of Compressors) regularlychanges the sequence of operation of the compressors.

Depressing key or will adopt the ASCmode and theword OFF will disappear from the display.- -LOW PRESSURE SWITCH DELAY ON START- -UP(single compressor units): fig S- -4.LPd (Low Pressure Delay) refers to the period afterstart- -up for which the intervention of the low pressureswitch is delayed (only in single compressor units).

NB: in twin- -compressor units, this item is not displayed; inthis case the low pressure switch delay is set by means oftrimmers in the additional alarm card.

It is shown at 180 seconds and can be changed using keysand . Depressing the key accepts the chosen valueand displays the following choice, which depends on thechosen hardware configuration:- -ELECTRIC HEATING STAGES (dipswitch N 1 OFF):fig S- -5.This refers to the number of stages of electric heating andcan be 1, 2, or 3. It is shown as 1, and can be changed usingkeys and . It must be set according to theconfiguration of the unit.

Depressing key confirms the selection and exits theconfiguration mode.

B. Chilled water units (dipswitch N2 ON) and/orC. Heating modulating valve: fig S- -6(dip switch N1 ON).

This displays the valve running (excursion) time, ie: the timetaken by the servomotor to pass from the fully closed to fullyopen position of the valve (and vice- -versa).The value shown is 150 seconds, and can be changed usingkeys and (it must be equivalent to the full runningtime of the motorized valve). Depressing key confirmsthe selection and exits the configuration mode.The reheat option using a modulating valve is notcompatible with the electric reheat.

11vers. 1.6 - - 24.06.96

SET DIFF

T- -1

INITIAL CHECKS

Each input reads the status (open or closed) of the contactconnected between it and the common (terminal 1). Thedata acquisition system is of the fail-safe type: the normalstatus is closed contact so that any faulty connections or badcontacts are immediately recognized as faults.

For this reason, all inputs which are not in use must bebridged with the common (terminal 1), except for thedehumidification input which, if closed, activates coolingfor the purpose of dehumidification (see DIGITALINPUTS on page 7).

CONTROL START UP

The outputs of the control system are deactivated in theevent of insufficient airflow.

Therefore if tests are carried out in the absence of airflow itis necessary to temporarily replace the PTC flow sensor witha resistor of 330- -4W (or to bridge the pressuredifferential switch FS, already connected to terminal 8 and 9across a resistor of 330- -4W).

WARNING :Do not short circuit the 8 and 9 inputas this could result in damage to the controller.

Put power on to the system. If everything is correct, thecontrol system starts up as follows:- - the yellow LINE LED illuminates (~LINE);

- - depressing key activates output 1 (starting the fans)and the green SYSTEM ON LED lights;- - the reading of the ambient temperature sensor appears inthe centre of the display, the setpoint appears in thebottom left- -hand corner and the differential appears inthe bottom right- -hand corner (see fig T- -1).

ADJUSTMENTS AND SETTINGS

ADJUSTMENT OF THE SENSOR

An algorithm manipulates the signal provided by thetemperature sensor in order to provide a perfectly linearcharacteristic: the sensor offset adjustment trimmer (seetrimmer in fig. C- -4, page 6) permits the temperaturereading to be calibrated, using a standard thermometer, inorder to obtain the level of precision which the resolution ofthe control enables, ie: to a tenth of one degree.

ADJUSTMENT OF THE PTC AIR FLOWSENSOR SENSITIVITY

The factory setting normally provides the best operation,therefore, if adjustment of the sensitivity should benecessary, it must be carried out in successive steps withsmall variations in the setting of the trimmer (see fig.C- -4, page 6); a counterclockwise rotation of the trimmercauses an increase of the sensitivity (earlier low airflowalarm condition).

12 vers. 1.6 - - 24.06.96

SET DIFF

T- -1

SET DIFF

T- -2

SET DIFF

T- -3

RANGE OF FACTORY SETTINGS

The mP3 controller is factory set to the default values shownunder PRESET in the table below.

These values can be modified according to requirementswithin the ranges defined by the minimum and maximumlimits in the table.

VALUE PRESET MIN MAX

Ambient temperature C 23.0 12.0 32.0

Differential band C 3.0 1.0 10.0

Integral time (1) s 900 100 1500

High temperature alarm C 30.0 10.0 50.0

Low temperature alarm C 10.0 5.0 30.0

Compressor low pressureswitch delay (2) s 180 0 300

Valve excursion time (3) s 150 60 300

(1) Adjustable only via serial line(2) Single compressor version(see SOFTWARE CONFIGURATION)

(3) Only with hot or chilled water valve(see HARDWARE CONFIGURATION)

ADJUSTMENT OF TEMPERATURE SETPOINT

In normal operation the display shows the values of thesetpoint and the differential (sensitivity if the control isP + I) : see fig T - - 1.

The key selects the value to be adjusted. Depressedonce it selects the setpoint (the figure in the display starts toflash).

Keys and are then used to adjust the value within thepermitted range (from 12 to 32 C ); depressing the keyagain confirms selection of the new value and goes on to theselection of the differential (which starts in turn to flash).

The permitted range for the differential band is 1 to 10C.

ADJUSTMENT OF THE HIGH AND LOWTEMPERATURE LIMIT ALARMS

The high and low temperature limits are those which, whenreached, give rise to the AMBIENT alarm signal.

They are detected by the standard control sensor and areignored for the first 10 minutes of operation after thestart- -up of the unit.

In order to access the relevant settings the key must bedepressed for about 5 seconds.

The display appears as shown in fig T- -2 indicating the highair temperature alarm limit proposed of 30C which can beadjusted between 10 and 50 C (with keys and ).

Depressing key again confirms acceptance of the valueand goes on to the next choice (see fig T- -3 ) which is the lowair temperature alarm limit proposed of 10C which can beadjusted between 5 and 30 C ( with keys and ).

Depressing key again confirms acceptance of the valueand exits this option (returns to the display of the actualambient air temperature).

13vers. 1.6 - - 24.06.96

SET DIFF

R- -1

60sec.

360sec.

60sec.

>360sec.

60sec.

180sec.

A B C

AB

CTENSION

COOLINGREQUEST

COMPRESSOROPERATION

TENSIONE

RICHIESTADIFREDDO

MARCIACOMPRESSORE

R- -2

UNIT START UP

To start up the air conditioning unit the followinginstructions should be followed;

- -ensure that the main isolator of the electricalcompartment is closed and that the yellow LINE LED isilluminated;

- -press key : the green SYSTEM ON LED lights up andthe fan(s) start;NB: Since the program reads the keypad at intervals of afew tenths of a second, it can happen that the push of a keymay be ignored if pressure was not applied for longenough. In this case simply exerting greater pressure onthe key is useless and could even cause damage. It issufficient to simply press the key for longer until thesystem responds.- - the display shows the ambient temperature, the controlsetpoint (SET) and the differential band (DIFF) (see figR- -1);- -before initiating full control and monitoring of any alarmconditions, the controller waits 60 seconds for thetemperature sensor to stabilize at the average condition;- -after 60 seconds have elapsed the control actioncommences according to the appropriate logic shown inthe CONTROL DIAGRAMS on page 15.

In units with a modulating valve for hot or chilled water, assoon as the control is activated the valve is cycled to zero andthe appropriate LED lights up: HEATING for the hot watervalve and/or COOLING for the chilled water valve (seeCONTROL ALGORITHM FOR THE CHILLEDWATER VALVE on page 14).

If any alarm condition is signalled (by the appearance of analarm code and the siren sounding), refer to the ALARMSsection on page 17.

NB: in the event of a low airflow alarm , all the outputs aredeactivated.

CONTROL ALGORITHMS

The following is an outline of the control logic of the mostimportant components.

Compressor control algorithm (directexpansion units)

When the cooling function is provided by a compressor orcompressors (direct expansion units) the controller uses analgorithm which optimizes the operation throughmanagement of the on and off cycles, always trying tominimize mechanical and electrical stress on thecompressor(s).

The operation is as follows (see fig R- -2):

- -a minimum interval of 6 minutes between successive startsof the compressor;- -once started, a compressor is not stopped for at least oneminute;- -once stopped, a compressor is not restarted for at least 3minutes;- - in twin- -compressor units, the interval between onecompressor and the next starting is at least one minute;- - in twin- -compressor units it is possible to provideautomatic sequence changeover in order to balancerunning hours of the two compressors.

14 vers. 1.6 - - 24.06.96

Control Algorithm for the chilled or hotwater valveThe mP3 controller can pilot 3 way valves (one hot and onechilled water) fitted with activators of the 3 point floatingtype, ie: equipped with two control inputs, one for theopening and one for the closing of the valve.The algorithm utilized provides control of the degree ofopening of the valve in the same way as a modulatingservomotor with 0- -10 V or 2- -10 V signal.The modulation is achieved by propelling the actuator in theopening or closing direction for the length of time necessaryto reach the required degree of opening , on the basis of thefull excursion time from fully closed to fully open ( V.r.t - -valve running time) which is fed in when the control isconfigured.The signal to open or close is given when the deviationbetween the current degree of opening and that required ismore than 5 % (minimum variation threshold).The algorithm uses zeroing sequences which serve to avoidany OFFSET errors in the valve opening which couldotherwise be amplified in operation:- -when power is first applied (yellow LINE LED lit) theactuator is fully reset by giving a closing signal for the fullexcursion time plus 10% (the green COOLING LED is litfor the CW valve or the green HEATING LED for the hotwater valve);- -when the degree of opening is more than 90% or less than10% the valve is signalled to fully open or fully close for aperiod equal to 16 % of the total excursion time;- - if the valve remains in a position of more than 90% or lessthan 10% opening, the reset cycle is repeated every 600seconds.

15vers. 1.6 - - 24.06.96

CONTROL DIAGRAMS

NOTES ON THE CONTROL DIAGRAMS FORTHE RETURN AIR TEMPERATURE

The control can be configured in any one of 12 differentways, by means of the dipswitches and the relevant menu,depending upon the type of unit and its components (DXwith one or two compressors, CW, with electric or hot waterheating) and the choice dictates which of the 12 differentoutput configurations is used. (See following controldiagrams).

A - - DIRECT EXPANSION VERSION

A1- - 2 compressors; 3 stage electric reheat (fig. D- -1)The three stages of heating use two outputs as follows:- -HEATING 1 activates output 2;- -HEATING 2 activates output 3 and deactivates output 2;- -HEATING 3 activates both outputs 2 and 3 together.The LOW limit step intervenes during dehumidification(called for via input 4) as follows:- -when the lower limit of the band is reached ( - - 100%) theLOW LIMIT step is immediately activated whichoverrides the call for dehumidification stopping thecompressor;- - the step remains activated until the SET POINT isreached when dehumidification can be started again onlyif it is required and always in accordance with theminimum 6 minute interval between compressor starts.

A2- - 2 compressors; 2 stage electric reheat or on- -offhot water valve plus 1 stage electric reheat(fig. D- -2)

This control diagram only varies from the last in the controlof the HEATING stages as follows:- - HEATING 1 activates output 2- - HEATING 2 activates output 3.

A3- - 2 compressors; 1 stage electric reheat (fig. D- -3)

This control diagram only differs from the last in that thereis only one HEATING step which activates output 2.

A4- - 2 compressors; hot water modulating valve(fig. D- -4)

This control diagram differs from (D- -3) in that theHEATING step is replaced by the slope representing thevalve opening corresponding to the deviation of the actualair temperature from the set point (see page 14:CONTROL ALGORITHM FOR THE HOT WATERVALVE).

COOLING 1

COOLING 2

HEAT. 1

HEAT. 2

HEAT. 3

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

- -20%

100%

LOW LIMIT

50%- -40%

D- -1

COOLING 1

COOLING 2

HEAT. 1

HEAT. 2

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

- -30%

100%

LOW LIMIT

50%

D- -2

COOLING 1

COOLING 2

HEATING 1

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

100%

LOW LIMIT

50%

D- -3

COOLING 1

COOLING 2

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

100%

LOW LIMIT

50%

D- -4

0%

100%

16 vers. 1.6 - - 24.06.96

A5- - 1 compressor; 3 stage electric reheat (fig. D- -5)The control diagram is the same as D- -1 with a singleCOOLING step in place of two.

A6- - 1 compressor; 2 stage electric reheat or on- -offhot water valve plus 1 stage electric reheat

The control diagram is the same as D- -2 with a singleCOOLING step in place of two.

A7- - 1 compressor; 1 stage electric reheatThe control diagram is the same as D- -3 with a singleCOOLING step in place of two.

A8- - 1 compressor; hot water modulating valveThe control diagram is the same as D- -4 with a singleCOOLING step in place of two.

B - - CHILLED WATER VERSIONS

B1- - modulating valve; 3 stage electric reheat(fig. D- -6)

This control diagram differs from D- -5 in that theCOOLING step is replaced by the slope representing thevalve opening corresponding to the deviation of the actualair temperature from the set point (see page 14:CONTROL ALGORITHM FOR THE CHILLEDWATER VALVE).

B2- -modulating valve; 2 stage electric reheat oron- -off hot water valve plus 1 stage electricreheat

This control diagram only differs from D- -6 in that there areonly two steps of HEATING controlled as described in A2.

B3- -modulating valve; 1 stage electric reheatThis control diagram only differs from D- -6 in that there isonly one step of HEATING controlled as described in A3.

B4- -modulating valve; hot water modulating valve(fig. D- -7)

This control diagram differs from D- -6 in that theHEATING steps are replaced by the slope representing thevalve opening corresponding to the deviation of the actualair temperature from the set point.

DEHUMIDIFICATIONClosing of the contact connected to input 4 (betweenterminals 1 and 5 - - see DIGITAL INPUTS section onpage 7), activates the dehumidification cycle which involvescooling action as follows:- -single compressor version: the compressor is started and,depending on type of unit, either the dehumidificationvalve (if provided) is closed or the air flow rate is reduced(outputs 4 and 5 activated - - OUTPUT CONNECTORpage 7);- - twin compressor version : compressor 1 is started and thedehumidification valve is closed via the extra output onthe additional alarm card (see page 8).- -chilled water version : the chilled water valve is fullyopened (output 5 is activated for the time necessary forfull opening);Control of the dry bulb temperature is taken care of by theremaining heating and cooling resources and the LOWLIMIT step (see page 15).

COOLING 1

HEAT. 1

HEAT. 2

HEAT. 3

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

- -20%

100%

LOW LIMIT

- -40%

D- -5

100%

HEAT. 1

HEAT. 2

HEAT. 3

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

- -20%

LOW LIMIT

- -40%

D- -6

0%

DIFF

SETPOINT

T - - C

100%- -100%

0%

- -60%

100%

LOW LIMIT

D- -7

0%

100%

0%

17vers. 1.6 - - 24.06.96

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -1

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -2

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -3

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

HUMIDIF

AMBIENT

A- -4

ALARMS

All alarms remain inactive for the first 60 seconds ofoperation of the unit. During this period, having started thefans, the control system waits for the reading of thetemperature sensor to stabilize before commencing fullcontrol and signalling of any alarms.

Every alarm condition is signalled by:

- - an audible warning, from the built- -in siren;- - a visible warning, with red LED on the front of the panel,the appearance of an arrow symbol in the display alongsidethe appropriate item and also by the appearance in thecentre of the display of an alarm code (see example in figA- -1).

Depressing key mutes the audible alarm and the alarmoutput is deactivated but the alarm code remains in thedisplay, alternating with the ambient temperature valuegiven by the sensor.

Depressing key a second time, not less than 5 secondsafter the first, the alarm status is cancelled and, if the causeof the alarm has been rectified, the system returns to normaloperation; if not, the alarm cycle is repeated.

CONTROL SYSTEM ALARMS

These alarms indicate a malfunction of the control systemitself and stop its operation.

- - EEPROM MALFUNCTION (fig. A- -2)

This indicates the probable presence of corrupted data inthe memory, due to system write errors or to memorycorruption by electrical noise or other high intensityelectromagnetic disturbances.

To reset the alarm it is necessary to convalidate one of thecontrol settings using the key (see the method onpage 12: ADJUSTMENT OF TEMPERATURESETPOINT). After this operation it is advisable to check ifall the values of system configuration and control settingsare correct.

This alarm deactivates all outputs.

- - DEFECTIVE TEMPERATURE SENSOR(fig. A- -3)

This indicates a conversion error in the sensor reading, dueeither to a fault in the sensor or in the input circuits.

This alarm deactivates all heating and cooling outputs.

OPERATING ALARMSThese are the alarms related to malfunction of unitcomponents or to out- -of- -limit conditions.

- - AIRFLOW ALARM (fig. A- -4)

This is detected by the air flow sensor.

It has a dedicated input (terminals 8 and 9 of the inputconnector).

This alarm deactivates all outputs.

18 vers. 1.6 - - 24.06.96

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -5

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -6

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -7

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -8

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -9

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -10

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -11

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -12

SET DIFF

AIR FLOW

COOLING

HEATING

FILTER

DEVICES

AMBIENT

A- -13

- - COMPRESSOR LOW PRESSURE ALARM (fig A- -5)

Single compressor direct expansion units

Given by the low pressure switch of the compressor, whenthe suction pressure goes below the preset value.

From input 5, on opening of the contact.

When activated, it stops the compressor.

NB: This input is ignored for a period after compressorstart- -up, programmed via the appropriate menu.

- - COMPRESSOR HIGH PRESSURE ALARM (fig A- -6)

Single compressor direct expansion units

Given by the high pressure switch of the compressor, whenthe discharge pressure goes above the preset value.

From input 6, on opening of the contact.

When activated it stops the compressor.

- - COMPRESSOR 1 ALARM (fig A- -7)

Twin compressor direct expansion units

Given by the high or low pressure switch of compressor 1 viathe additional alarm card.

From input 5, on opening of the contact.

When activated it stops compressor 1.

- - COMPRESSOR 2 ALARM (fig A- -8)

Twin compressor direct expansion units

Given by the high or low pressure switch of compressor 2 viathe additional alarm card.

From input 6, on opening of the contact.

When activated it stops compressor 2.

- - ELECTRIC HEATING ALARM (fig. A- -9)

Given by the electric heating safety thermostat when thetemperature exceeds the preset value.

From input 1, on opening of the contact.

This alarm deactivates all heating outputs.

- - EXTERNAL DEVICES ALARM (fig. A- -10)

Given by input 3, coming from the hP3 humidity controland/or from the following optional alarms: water under floorsensor, ambient high/low temperature and humidityswitches, smoke/fire detectors.

Signal only.

- - CLOGGED FILTERS (fig. A- -11)

Given by the filter pressure differential switch when thepressure drop across the filters exceeds the preset value.

From input 2, on opening of the contact.

Signal only.

- - HIGH AMBIENT TEMPERATURE (fig. A- -12)

Given by the temperature sensor when the maximum limit,preset via the appropriate menu, is exceeded.

Signal only.

- - LOW AMBIENT TEMPERATURE (fig. A- -13)

Given by the temperature sensor when the minimum limit,preset via the appropriate menu, is reached.

Signal only.

19vers. 1.6 - - 24.06.96

FAULT FINDING

FAULT POSSIBLE CAUSE CHECK AND REMEDY

CONTROLLER DOES NOT START A) No power to electrical panel Check power supply;(yellow LINE LED does not light) Ensure isolator is closed.

B) No power to control panel 1) Check that controls circuit breaker is closed;2) Check that the auxiliary fuse has not blown(fuse holder in terminal block of electrical panel);

3) Check electrical connections(consult unit wiring diagram).

EEA ALARM A) Check data sum error 1) Refer to ALARMS section on page 17.2) Proceed as follows to re- -initialize theEEPROM:- - open all the circuit breakers in the electricalpanel;- - put power on to the controller, closing theauxiliary circuit breaker and simultaneouslydepressing both keys and ;

- -release keys and depress ;- -depress in sequence the following keys:, , , , ;

- -wait until the LEDs SYSTEM ON,COOLING, HEATING e ALARM; light up- -cut the power supply and then close all thecircuit breakers;- -restore power by closing the main isolator;- -start the control by depressing ;- -check the present values (see page 12).

3) If normal operation is not restored it meansthat the EEPROM must be faulty (see B).

B) faulty EEPROM (impossible to Replace the controller and return for repairs.deactivate the alarm)

SEA ALARM A) Temperature sensor not properly 1) Check connections and that terminals 10 and 11connected, disconnected or short are tightened (see page 7);circuited. 2) Check continuity of NTC sensor with a circuit

tester (at 25C it should have a resistance of10 k approx.) and replace if necessary.

B) Faulty control input circuits Replace the controller and return for repairs.

FLA ALARM APPEARS WITH A) Airflow sensor not properly connected, 1) Check connections and that terminalsFAN(S) IN OPERATION disconnected or short circuited 8, 230, 240 and 9 are tightened.

2) Check with a tester the continuity of the PTCsensor (at 25C it should have a resistance of50 k approx.) and replace if necessary; or:

3) (in units with the FS pressure differential switch)check with a tester the continuity of the resistor(330- -4W) connected to terminals 230 and 240of the electrical panel and replace if necessary.

B) The alarm circuit is faulty Replace the controller and return for repairs.

ALA ALARM A) Alarm coming from hP3 control Check the alarm code on hP3 control display(alarm from external devices) (see hP3 instruction manual).

B) Alarm coming from SAS sensor Check the alarm indication on SAS control fascia(water under floor) (on the right side of the electrical panel).

C) Alarm coming from other sensors 1) Check the presence of smoke or fire(if the relevant sensor is fitted);

2) Check if any room temperature or humidityhigh or low limit was exceeded (if the relevantsensors are fitted).

IINTERCONNECTION OF UNITS WITH mP3 CONTROL

PREFACE(please refer also to the mP3 instruction manual)

The mP3 microprocessor control retains in its memory the ON orOFF status of the air conditioner: restoration of the power supplycauses units which were on to restart; while units which wereoff before power was cut will remain off.

Therefore, in order to provide remote control (starting andstopping bymeans of a remote contact) of a unit with mP3 control,it is sufficient simply to cut the power supply to themicroprocessor(terminal 19).

By utilizing the output from the alarm relay (NO - - normally open- - contact between terminals 22 and 21 and NC - - normally closed- - contact between terminals 22 and 23 at the rear of the mP3panel) it is possible to cause the start- -up of standby units in theevent of an alarm in units normally running.

In order to provide this type of interconnection the wiring diagramfor mP3 controlled air conditioners has to be modified as shown infigure 1:

- - adding an auxiliary relay RS which, when fed by a remotecontact, will cause the unit to start by the closing of its own NOcontact;

- - adding an auxiliary relay RAG, the NC contact of which is usedto provide the start signal to a standby unit in the event of:

a) intervention by the alarm relay in the control panel;

b) control circuit power failure in the electrical panel;

c) microprocessor malfunction.

The added pair of terminals 20- -50 (remote start) and 51- -52(alarm signal) are used for wiring the interconnecting circuits.

RS

RAG

G (19)

G0 (20)

20

0

40

RS

20

50

23 21

22

mP3ALARMRELAY RAG

51

52

Fig.1

A simplier circuit is shown in fig. 2, in wich the mP3 alarm contactis directly connected to start- -up the stand- -by unit (no control incase of auxiliary circuit power failure).

RS

G (19)

G0 (20)

20

0

40

RS

20

50

23 21

22

mP3ALARMRELAY

51

52

Fig.2

A) Direct interconnection of 2 units of which one, preselected, is on standby

mP3 mP3

51 52

UNIT 1 STANDBY

20 50

In the event of any alarm condition, the control of the normallyrunning unit closes the contact between terminals 51 and 52 andthereby feeds the remote control relay for the standby unit.

B) Direct interconnection of a number of units of which, one, preselected, is on standby

51 52

UNIT 1

51 52

UNIT 2 STANDBY

20 50

mP3 mP3 mP3

As above, with any number of run units and one standby unit.

In the event of any alarm condition, the control of one of thenormally running units closes the contact between terminals 51and52 and thereby feeds the remote control relay for the standby unit.

II

C) Interconnection of 2 units of which either one can be chosen as standby

51 52

UNIT 1 UNIT 2

51 52

mP3 mP3

20 50 20 50

TS

1 2

The selector, TS, is a user- -installed and wired switch whichpermits the choice of which of the two units is running and whichis on standby at any time.

Using selector TS, the chosen run unit can be started and theother automatically becomes standby.

D) Interconnection of a number of units where selection of run, standby or off status can be made for each unit

Each selector TSx permits the status of the corresponding unit tobe selected as run, standby or off.

The standby units are automatically started in the event of anyalarm in the run units.

In the diagram: unit 1 is running; unit 3 is on standby. If there is an

alarm on unit 1, the contact RRclosing between 20 and 50will startunit 3.

The RR relay must have a delayed action of at least 1 second.

z N.B. The electric control panel (shaded in the diagram) containingthe TSx selectors and theRR relay must be provided by the user orhis contractor.

TS1

0N S

OFFNORMAL STAND- -BY

RR

TS2

0N S

RR

RR

51 52

UNIT 1 UNIT 2

51 52

mP3mP3

20 5020 50

mP3mP3

TS3

0N S

RR

TSn

0N S

RR

51 5251 52

20 5020 50

UNIT 3 UNIT n

24V~

Y

B

III

E) Interconnection of a number of units where selection of run, standby or off status can be made for each unit- - Version with automatic switch- -off of unit in alarm - -

R1,...,n : latching auxiliary relays if unit 1,...,n goes into alarm

RESET : reset button for latching alarm relays

RR : auxiliary relay activated by each Rx

TS1,...,n:3 position selector switches for each unit:- - NORMAL (unit n running, switched off by Rn)- - OFF (unit always switched off)- - STAND- -BY (unit off, started by RR)

TS1

0N S

R1

OFFNORMAL STAND- -BY

L1

R

R1

R1

RR

RESET

R1 R2 R3 Rn

RR

24V~

UNIT 1

51 52

mP3

20 50

mP3

TS2

0N S

R2L2

R

R2

R2

RR

UNIT 2

51 52

20 50

mP3

TS3

0N S

R3L3

R

R3

R3

RR

UNIT 3

51 52

20 50

mP3

TSn

0N S

RnLn

R

Rn

Rn

RR

UNIT n

51 52

20 50

Y

B

The status for each unit can be individually selected bymeans of theTSx selector switch as: run, off or stand- -by.

The stand by units are automatically started in the event of anyalarm in the run units.

In the diagram: unit 1 is running; unit 3 is on standby. If there is analarm on unit 1, R1 (latched) switches off unit 1 and feeds the relay

RR, the contact of which starts unit 3 closing between terminal 20and 50.

The Rx relays must have a delayed action of at least 1 second.

z N.B. The electric control panel (shaded in the diagram) containingthe TSx selectors, the Rx relays, the Lx lamp and theRR relay mustbe provided by the user or his contractor.