THERMOCOUPLES

� GENERAL

Straight ThermocouplesStraight thermocouple with metal and ceramic protecting tubesare widely used in a variety of processes between –200°C and2320°C The maximum operating temperatures given in thecatalogue apply to the air where there are no corrosive gases.

L-type of ThermocouplesL-type thermocouples are usually used in temperaturemeasurement of salt baths and metal melts. The reason forusing of angled type thermocouples is to protect the headfrom the heart and the corrosive gases on the bath.

Inset Type ThermocouplesInset type of thermoucouples are inserted to the secondaryprotecting tubes to have longer life-time in processapplications. Inset consist of an inset tube stem or alternativelyof mineral isolated thermocouples terminated with a ceramicterminal block connected to a metal flange.

Portable type ThermocouplesPortable type thermocouples have a comprehensive range ofapplications. Portable type thermocouples can be used inmeasuring the temperatures of both ambient and surfaces.

Exhaust ThermocouplesExhaust thermocouples have special mounting forms inaccordance with the characteristics of process. Generally theyare mounted with fixed cables.

Bayonet Type ThermocouplesThese thermocouples are mounted with fixed cables andsecured with spring compression to their location ofinstallation. The bayonet type thermocouples can not used forliquids or humid conditions.

Mineral Insulated ThermocouplesMineral Insulated Thermocouples can be used in various

processes at different temperatures such as;• in containers, pipelines, apparatus and machinery, also in

laboratories and experimental plant• in gaseous and liquid media such as air, gases, water, oil, etc.• in low-pressure areas, at low rates of flow

ThermowellsIn general the thermowells chosen for the installation isgoverned mainly by the corrosion conditions the well will face.The high polish given to all stainless wells provides maximumcorrosion resistance. Occasionally, the material considerationis one of the strength rather than corrosion resistance. Whenordering flanged thermowells, be sure to specify the flangefully. Use a sketch or drawing of both flange and well forordering stage.

� DESIGN AND SELECTION

In order to increase the life-span of thermocouples thematerials for the thermocouple, element wire insulator,protecting tube and connection head must be selectedaccording to operating conditions. The maximum operatingtemperatures given in the catalogue apply to the conditionswhere operating medium is air. Although the exceeding of themaximum temperature limits specified for short periods do noteffect the results, they will reduce the life of thethermocouples corrosive substances in the process also causesthe upper temperature limit to be lower for the protectingtube.

� THERMOCOUPLE STANDARD

EMF characteristics of the thermocouples meeting DIN 43710and IEC 584 are given in Thermocouples Supplementary Notessection concerning thermocouples. According to the customerrequirements, Elimko can manufacture thermocouples in otherstandards or special types.

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� PROTECTING TUBES

Protecting tubes must be selected in accordance with theconditions of the process. As a rule, metal protecting tubes areused up to 1200°C and ceramic tubes are used over 1200°C.In order to prevent the thermocouples element wire frombeing effected by corrosive gases and increase the life span ofthe thermocouple, a second ceramic protecting tube is placedinside. Ceramic protecting tubes being used as gas-tight havebelow given specifications;

KER 610 Better gas-tight characteristics High heat resistanceHigh aluminium oxide percentageMore economical than KER 799

KER 799 Much better gas-tight characteristicsMaximum heat resistancePure aluminium oxyde pers entageBetter and more expensive than KER 610

In L-type thermocouples protecting tubes are connected to thebody in two ways. Si-Cr and Si-Ni type of ceramics areconnected in TC06 drawing code and the others are in TC07drawing code.

Since the mineral insulated thermocouples have a specialstructure, they do not have the opportunity to be used withvarious cases with different alternatives like otherthermocouples. The protecting tubes of mineral insulatedthermocouples can be inconel or 316 stainless steel. Elimkostandards are usually inconel and are used up to 1200°C.Thermocouples could be welded with or without grounded atthe end point. It is required to give the details at orderingstage.

� CONNECTION HEADS

Element wires and compensation cables are connected in rightpolarities to the ceramic terminal in connection head whichthe thermocouple tubes are fastened A-type large and B-typesmall heads in standards are used. Connection heads areavailable having dimensions according to DIN 43729. Metalheads are suitable for a maximum ambient temperature of200°C.

� MOUNTING METHOD

The thermocouples given in detail in this catalogue aregenerally considered to be connected by means of anadjustable flange or adjustable bushing. These mounting partscan be supplied when customers specify exact needs.

� INSTALLATION INSTRUCTIONS

It is recommended to use the maximum immersion length ofthermocouple assembly, thus keeping measuring errors causedby heat transfer along the protecting tube and wires to aminimum. In order to prevent the long tubes from bending, itis advisable to mount them upright position or to prodvide forappropriate support. A compensating cable should be usedbetween the thermocouple head and the instrument. Please besure that a proper compensating cable is selected and theconnection is made properly. In order to get accuratemeasurement, insertion length of the thermocouple should benot less than 10 times of the external diameter. For the L-typethermocouples, the head of the thermocouple should be awayfrom the corrosive gases over the bath level.

For mineral insulated thermocouples insertion length of thethermocouple can be 5 times of its external diameter in case ofliquids, and 20 times of its external diameter in case of gases.

Minimum bending-radius changes according to the diameter ofthe mineral insulated thermocouples.

� STANDARD TYPESThe standard types ordered by the customers are delivered inshort periods and at reasonable prices provided that thepriority is given to the competition factors.

To chose the standard type of thermocouples are easy byusing code list and can be delivered from stock.

� SPECIAL TYPESSpecial types according to the application can be ordered bygiving the answers of the questions below.

a. Applicationb. Continuous and maximum operating temperaturesc. Technical drawings with size, diameter, and other detailsd. Product code number, if ordered previouslye. Pressure and flow data if knownf. Chemical corrosion factors

Please try to fill in the questionary form of thermocouples insupplementary notes.

� SPARE PARTSAll kinds of spare parts for thermocouples can be ordered byusing the selection table in the catalogue. According to thestock level, the spare parts may be delivered from stock orwithin a certain delivery period.

� REPAIRRepair of the thermocouples is not economical if almost all theelements are defective. As stated in the thermocouple sparessection, only when either the tube or the element wire isworking the other component can be repaired using spareparts.

� HOW TO ORDERa. Standard typesStandard types are coded by using drawing number and 7different groups of alphanumeric characters

b. Special TypesSpecial features are defined in the 7th digit or by additionalinformation added to the end of the 7th digit. Fully specialtypes are subjected to a different coding.

ExampleTC01 - 1 K 2 N 22 - 50 PY

1 2 3 4 55 - 66 77

• Drawing nr TC01• With single element• NiCr-Ni• Element wire dia 2mm• Seconder protection 1.4841• Seconder protection 22 mm• Immersion length 500 mm• Gas-tight KER 610.

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Drawing number

1 Number of elements (single-double)

2 Type of element

3 Diameter of element wire

4 Protecting tube

5 Diameter of protecting tube

6 Immersion length

7 Special features

Drawing nr. 1 2 3 4 5 - -6 7

TC01 - - -1 K N2 22 50 PY

Drawing nr. TC01 TC02 TC03 TC04 TC05 TC06TC07 TC07-A TC08 TC09 TC10 TC11 TC12 TC013 TC14 TC15 TC16

Thermocouples are coded with different drawingnumbers.

1- Single elementDouble element

(1)(2)

1 or 2 comes in the 1.digit in a accordance with thenumber of the elements of thermocouple

2- Type of element EL‹MKO CODE STANDARD CODEU Cu-Const U*L Fe-Const L*

T Cu-Const TJ Fe-Const JK NiCr-Ni KE Cr-Const EN Nikrosil-Nisil NS Pt%10Rh-Pt SR Pt%13Rh-Pt RB Pt%18Rh-Pt B

In 2. digit, corresponding letter represents the typeof the element

*According to DIN 43710 standards the others are IEC 584

3- Diameter of theelement wire

1) 1 mm2) 2 mm3) 3 mm4) 0.35 mm

5) 0.5 mm6) 1.38 mm 7) 1.5 mm8) 6.0 mm M/I

9) 4.5 mm M/I10) 1.5 mm M/I11) 8.0 mm M/I

special

In 3. digit diameter of the element wire is given. Itrefers to the temperature which thermocoupleworks. In general, the diameters of 0.35mm and0.35mm and 0.5mm are for PtRh-Pt elements

5- Diameter of theelement wire

06 18 4508 2009 22 11 2414 2615 30 Note: These dimensions are in mm

In 5. digit, the diameter of the protecting tube isgiven. The diameter is selected by consideringdifferent factors. The diameters given here arestandard dimensions. Note: 5. digit has two digits.

6- Thermocouple length (immersion length)

10 71 Note: These dimensions are in cm16 100 18 120 25 140 Only inset heights are in mm35 16050 200

In 6.digit, the immersion length is given. In order toensure an account measurement, immersion lengthof the thermocouples should be at least 6 or 10times of the protecting tube diameter.Note: 6. digit has two digits.

7- Special Features P Primary PY Primer KER 610R Mounting Bush PZ Primer KER 799F Flange EX Exproof headI Insulator Tr TransmitterO Special S Socket S1 S2 S3

In 7.digit the corresponding character is given. Theseletters present such as primary protecting tube,coupling, flange etc. For special conditions inaddition to standards "O" letter is printed.

4- Protecting tube X 530Y 610Z 799

M 1.4772N 1.4841O 1.4867R RefraxS Si-CrT TitaniumQ Quartz

A Al-25B BrassC C-2D St-35.8F Pure IronG GraphiteI Inconel

P 1.4301 (304)E 1.4401 (316)H 1.4404 (316L)J 1.4541 (321)K 1.4571 (316TI)L 1.4749L 1.4762

In 4. digits, the material of the protecting tube isgiven by selecting in accordance with the process.Please reference to the Thermocouple selectiontable for an appropriate selection

EL‹MKO STRAIGHT THERMOCOUPLE CODING

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EL‹MKO STRAIGHT THERMOCOUPLE ASSEMBLIES

EL‹MKO L-TYPE THERMOCOUPLE ASSEMBLIES

TC01 TC02 TC03 TC04 TC05 TC30

EL‹MKO L-TYPE THERMOCOUPLE CODING

TC06 TC07

In determining codes for L-type thermocouple,straight-type thermocouple coding list is used.Drawing number of L-type thermocouple canbe TC06 or TC07. As seen in the drawingbelow L1 is the insertion length. In standardtypes, when L1 is determined, L2 is determinedautomatically. Special requirements should bespecified additionally. L1 versus L2 lengths aregiven in the table.

L1 lengthchosen inthe code

L1= 31 cmL1= 51 cmL1= 71 cm

L1= 30 cmL1= 50 cmL1= 71 cm

L2= 33 cmL2= 50 cmL2= 50 cm

L2= 33 cmL2= 50 cmL2= 57 cm

standard L2versus L1

L3 (mm)

L1xL2= 310x330 mmL1xL2= 510x500 mmL1xL2= 710x500 mm

L1xL2= 300x330 mmL1xL2= 500x500 mmL1xL3= 710x570 mm

L1xL2 (mm)

Dra

win

gnr

.T

C06

TC

07

460 mm660 mm860 mm

TC07-A

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EL‹MKO PORTABLE TYPE THERMOCOUPLE ASSEMBLIES

EL‹MKO PORTABLE TYPE THERMOCOUPLE CODING

In determining codes, for portable type of thermocouple straight-type thermocouple coding list is used. Drawing number of portabletype of thermocouples can be chosen below given assembles according to the application.

TC08

TC10

TC10-Y

TC10-YU

TC10-I

TC10-H

TC15

TC09

TC10-1

TC10-YA

TC10-YD

TC10-HD

TC14

TC15-K

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TC17TC16

EL‹MKO EXHAUST AND OTHER TYPE T/C ASSEMBLIES

EL‹MKO EXHAUST AND OTHER TYPE T/C CODING

These types of thermocouples are coded with special figures. Standard code list may be used as well. After the drawing number iswritten, other numbers and letters may be drawn from the coding list of straight type thermocouples.

EL‹MKO INSETS AND THERMOCOUPLES WITH INSETS ASSEMBLIES

EL‹MKO INSET THERMOCOUPLES

Insets can be used for installation into assemblies of different design. They can be exchanged easily during operation the insetsdescribed in this catalogue can be used for installation in to TC03 and TC04 types.

In determining codes for insets, straight-type thermocouple coding list is used. Drawing number of inset is TC05. Only exception isthe inset length is given in mm instead of cm.

Example: TC05-1K1P06-305 Length is in mm only for insets

TC11 TC12-1

TC03 TC04 TC05

TC12-2 TC12-11 / TC12-21

TC13 TC20

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EL‹MKO BAYONET TYPE THERMOCOUPLE ASSEMBLIES

EL‹MKO BAYONET TYPE THERMOCOUPLE CODING

The bayonet thermocouples are coded as follows:Drawing number

1 Number of elements (single-double)

2 Type of element

3 Diameter of protecting tube

4 Immersion length

5 Cable Length

Drawing nr. 1 2 3 4 5

BT01 - 1 J -06 3 K10

Drawing nr. BT01, BT02, BT03, BT04, BT05, BT06 Bayonets are coded with different numbers

1- Single elementDouble element

(1)(2)

1 or 2 comes in the 1.digit in a accordance with thenumber of the elements of thermocouple

2- Type of element EL‹MKO CODE STANDARD CODEU Cu-Const U*L Fe-Const L*

T Cu-Const TJ Fe-Const JK NiCr-Ni K

In 2. digit, corresponding letter represents the type ofthe element

*According to DIN 43710 standards the others are IEC 584

3- Diameter of theprotecting tube

04 (in mm)050608

In 3. digit the diameter of the protecting tube is given.Generally protecting tubes used are brass or stainlesssteel. Note: The third digit has two digits.

5- Cable length K10 1 mK15 1.5 mK20 2 mK25 2.5 mK30 3 m...

In 5. digit the cable length is given as K10, K15. K10means a cable length of 1 meter, K25 means 1.5meters

4- Bayonet length 2 (in cm)345...

In 4. digit the immersion length is given. Standardlength is 30 mm.

BT01

BT02 BT03

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EL‹MKO MINERAL INSULATED THERMOCOUPLE CODING

The mineral insulated thermocouples are coded as follows:Drawing number

1 Number of elements (single-double)

2 Type of element

3 Diameter of protecting tube

4 Immersion length

5 Special Features

Drawing nr. 1 2 3 4 5

MI01 - 1 J -60 50 F

MI01, MI02, MI03, MI04, MI05, MI06, MI07, MI08 Mineral insulated thermocouples are coded withdifferent numbers

1- Single elementDouble element

(1)(2)

1 or 2 comes in 1. digit in accordance with thenumber of elements of thermocouple

2- Type of element EL‹MKO CODE STANDARD CODEL Fe-Const L DIN 43710J Fe-Const J IEC 584K NiCr-Ni K IEC 584

In 2. digit, corresponding letter represents the type ofthe element

3- Protecting tubediameter

15 � 1.5 mm30 � 3 mm45 � 4.5 mm60 � 6 mm

In 3. digit the diameter of protecting tube is given. Note: The third digit has two digits.

5- Special features R Mounting BushF FlangeO SpecialTr TransmittersME Miniature Socket (Male)SE Standart Socket (Female)MD Miniature Socket (Male)SD Standard Socket (Female)

In 5. digit the corresponding character is given. Theseletters present such as mounting bush, flanges,sockets, etc. for special types, in addition to standarts"O" letter is printed.

4- Thermocouple length

16 (in cm)25405071100 Note: Only inset lengths are in mm.

In 4. digit the immersion length is given. In order toensure an accurate measurement, immersion length ofthe thermocouples should be at least 5 times forliquids, at least 20 times for gases. Note: 4. digit has two digits.

Drawing nr.

BT04 BT06

BT05

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EL‹MKO MINERAL INSULATED THERMOCOUPLE ASSEMBLIES

MI01 MI02

MI03 MI04

MI05 MI06

MI07 MI07-I

MI07-Y MI07-YA

MI07-I MI07-H

MI07-HD MI08

The mineral insulated Thermocouples have certain diameters onthe standards. The minimum diameters that thesethermocouples can be bended are limited. If bending curveexceeds these dia meters, the thermocouple is damaged. It canbe broken. Because of this reason, attention should be paidwhen bending the mineral insulated thermocouples. The limitsare given a table.

Fe-Const or NiCr-Ni

Outer Diameter Minimum Bending ApproximateDiameter Element wire diameter

1.5 mm 8 mm 0.18 mm

3.0 mm 15 mm 0.45 mm

4.5 mm 23 mm 0.7 mm

6.0 mm 30 mm 1 mm

8.0 mm 36 mm 1.2 mm

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