Thermoelectric temperature transducers

Thermoelectric temperature transducers (thermocouples, temperature transducers) – CrAl thermocouple, Chromel-Copel thermocouple are used for temperature measurements and control of liquid, solid, gaseous and granular media for various industrial applications. The thermocouples are used together with ZET 7020 TermoTC-485 and ZET 7120 TermoTC-CAN digital temperature sensors.

Pt Thermoelectric temperature transducers (thermocouples) S, R, B types

External view	Product name	Brief description
	S, R -53-1 B‑53-1	Used together with ZET 7020 TermoTC-485 and ZET 7120 TermoTC-CAN digital temperature sensors for temperature measurements in chemically inert and chemically aggressive environments that are safe to outer fittings.
	S, R-53-3 B‑53-3	Used together with ZET 7020 TermoTC-485 and ZET 7120 TermoTC-CAN digital temperature sensors for temperature measurements in chemically inert and chemically aggressive environments that are safe to outer fittings.

Measuring system

Digital temperature sensor ZET 7020

Digital temperature sensor ZET 7120

Thermocouples transform temperature impact into electrical signal that should be additionally measured for the purpose of temperature value determination. Thermocouple together with the measuring module form intelligent temperature sensor, i.e. the user receives ready data that does not require any additional processing. Measurements results are transmitted in digital format via RS-485 (using ZET 7020 TermoTC-485 module) or via CAN interface (using ZET 7120 TermoTC-CAN module). The measurements results can be used for automated temperature control, as well as be received by temperature recorder  or displayed at digital or virtual (PC) indicator.

How to buy thermoelectric temperature transducer?

If you want to buy a measuring system as well as to receive informational support, please contact our managers (tel. 8(495)739-39-19 – multichannel) or use the dialogue window in the right bottom part of the web-page. Our technical specialist will contact you as soon as possible.

Product name	Brief description
ZET 7020	Digital resistive temperature transducers ZET 7020 TermoTC-485 are used for temperature measurements in liquid, gaseous and granular media that are safe to outer fittings.
ZET 7120	Digital temperature sensor consists of a thermocouple and ZET 7120 TermoTC-CAN module, performing sensor signal conversion to a temperature value.

CrAl and Chromel-Copel thermoelectric temperature transducers: technical specifications 

The thermocouples are further classified into various groups depending on particular climatic version and resistance to mechanical and climatic impact.

Thermocouples temperature measurement range:

• For CrAl type thermocouples— from – 40 to +1200 °С;
• For Chromel-Copel type thermocouples — from – 40 to +600 °С

Nominal static characteristics, their indexes, thermocouple wire material data are shown in the table below:

Thermocouple type	NSC	Thermocouple wire material
		Positive leg	Negative leg
CrAl thermocouple type	(K)	chromel	alumel
Chromel-Copel thermocouple type	(L)	chromel	copel

Positive thermocouple wire is marked with red color. There are two tolerance classes for thermocouples.

In the Table below you can find temperature tolerance values for corresponding thermocouples classes (of CrAl and Chromel-Copel type):

Thermocouple type	Class	Temperature range, °С	Limit value of deviation from NSC, °С
CrAl	1	from−40 to 375	1,5
		over 375 and up to 1000	0,004·|t|
	2	from−40 to 333	2,5
		over 333 and up to 1200	0,0075·|t|
Chromel-Copel	2	from−40 to 300	2,5
		over 300 and up to 800	0,0075·|t|

where |t| — is absolute temperature value, °С

Thermoelectric temperature transducers (thermocouples) of CrAl and Chromel-Copel type structurally consist of two different thermocouple wires (Chromel-Alumel or Chromel-Coppel correspondingly). The thermocouple wires are separated by high-temperature insulation and welded into measuring junction at one side. Protection fittings are made of heat- and corrosion- resistant steels or ceramics (for the purpose of temperature measurements in extremely aggressive high-temperature environments).The exposed ends of the thermocouple wires are connected to the application head or are joined to an output cable. Measuring junction can be insulated or non-insulated from the protective casing. Transducers may have two measuring junctions – two thermocouples of the same type placed into a single package (in this case the product index specifies the measuring junctions amount – 2). If transducer head is made of molding compound, which allows to use it in chemically inert environment at the temperature up to 120°С; in the case if polyamide is used – the operational temperature range is up to 80°С. Maximum output cable diameter is up to 10 mm. Each wire of the cable is mounted on М4×0,7 screw unit. Metal head made of silumin alloy is used in chemically inert environment at the temperature up to 300°С. Maximum output cable diameter is up to 12 mm. Each wire of the cable with a diameter less than 1,2 mm is mounted on М4×0,7 screw unit.

Transducers (thermocouples) of S,R and B types: technical specifications. 

Nominal static characteristics

Thermocouple type	NSC index
Тype S thermocouple	S
Type R thermocouple	R
Type B thermocouple	B

Acceptable deviations from NSC

NSC index	Tolerance class	Operational temperature range, °С	Acceptable deviations from NSC limits, °С
S	1	0…1100	± 1,0
R	2	1100…1300	± 1,0 +0,003(t-1100)
		0…600	± 1,5
		600…1300	0,0025·t
B	2	600…1700	± 0,0025·t
	3	600…800	± 4,0
		800…1700	± 0,0050·t

Thermocouple wires diameter

Thermocouple type	Thermocouple wire diameter, mm
S, R	0,4 (0,5) for Pt90Rh10 (+) and 0,5 for Pt (-) 0,4 (0,5) for Pt87Rh13 (+) and  0,5 for Pt (-)
B	0,4 (0,5) for Pt70Rh30 (+) and  0,5 for Pt94Rh6 (-)