Temperature Sensors

Sensor Types

Thermistors

For Ambient Temperatures
Thermistors are ideal for ambient temperatures as they combine fast response time and accuracy. Range extremes are -50°C to + 150°C. Long cable lengths can be used.

Type U: 2000 ohms at 25°C (accuracy +/-0.1°C over the range 0 to 70°C)

Thermocouples

Type Names of Materials Useful Range
J Iron (+)
Constantan (-)
200 - 1400°F
95 - 760°C
K Chromel (+)
Alumel (-)
200 - 2300°F
95 - 1260°C
T Copper (+)
Constantan (-)
-330 - 660°F
-200 - 350°C

PRTs (Platinum resistance)

Accurate at High Temperatures
PRTs are best suited for measuring temperatures down to -100°C and up to +600°C with good long term stability and accuracy. Due to the small change in resistance of PRTs, cable resistance can affect the accuracy of the sensor. Three or preferably four wire cables should be used and long lengths should be avoided. Eltek products support only PT100 Platinum Resistance Sensors.

Probe Types

Items marked with a * are available on quick delivery.

General Purpose

Robust, fast response, stainless steel, rounded end probes. Typical applications include air, vapours, liquids, powders, fridges, freezers, food...

CS*
Sensor Code Cable Code Connector
Thermistor U VL 0*, 1*
Thermocouple J, K, T NL, MT,FG 0, 1, 3
Pt100 P4 (4 Wire) CA, CB 0
Length 125mm, dia. 4.8mm
CM*
Sensor Code Cable Code Connector
Thermistor U VS 0*, 1*
Thermocouple J, K, T NL, MT, FG 0, 1, 3
Thermocouple T NS 0, 1, 3
Length 50mm, dia. 3.2mm
CMS*
Sensor Code Cable Code Connector
Thermistor U VS 0*, 1*
Thermocouple J, K, T NL, MT, MG 0, 1, 3
Thermocouple T NS 0, 1, 3
Length 25mm, dia. 3.2mm
CT*
Sensor Code Cable Code Connector
Thermistor U VL 0*, 1*
Thermocouple J, K, T NL, FG 0, 1, 3
Pt100 P4 (4 Wire) CA, CB 0
Length 50mm, dia. 4.8mm
Exposed Junction Thermocouples
Probe Code Thermocouple Cable Code Connector
TH-J CODE J 0, 3
TH-K CODE K 0, 3
TH-T CODE T 0, 3
Thermocouple sensor at end of cable (conductors are exposed and welded at tip). Fast response, low cost. See cable information for temperature and length details.
Surface Temperature

Sensor mounted on either copper or stainless steel base. Typical applications include radiators, pipes, pumps, motors...

EU* (copper base) / EUS (st. st. base)
Sensor Code Cable Code Connector
Thermistor U* VS, VL 0*, 1*, 2
Thermocouple J, K, T NL, NS, MT 0*, 1*, 3
length 18mm, max width 8.5mm
Room Temperature

Sensor assembly mounted on aluminum bracket. Removeable black plastic globe to allow for the effect of radiant heat. Typical applications include radiant temperature and air temperature measurements.

AG
Sensor Code Cable Code Connector
Thermistor U VL 0, 1, 2
Thermocouple J, K, T NL 0, 1, 3
Globe dia. 36mm
Insertion Probes

Stainless steel sheath with pointed end and choice of handle for easy insertion and withdrawal into solid material. Typical applications include frozen food, soil and ice...

CMP
Sensor Code Cable Code Connector
Thermistor U VS 0, 1, 2
Thermocouple T NS, MT 0, 1, 3
length 50mm, dia. 3.2mm (no handle)
Soft Insertion Probe

Sensor sealed into smooth round ended flexible translucent PVC tubing which is smoothly fused onto cable. For delicate applications requiring flexible soft insertion.

Note: this product is not a medical device and is not intended for use with humans or animals.

Code Thermistor Code Length (mm) Dia (mm) Cable Code Connector
REC U, UU 100 5.0 VL 0, 1, 2
REC (small) U, UU 50 3.0 VS 0, 1, 2
OES U, UU 394 5.0 VL 0, 1, 2

Lead Types

Code Description Operating range Maximum dia. (mm) Maximum length (m)
VS PVC small coaxial, lightweight, water resistant, flexible -10 to 105 2.1 10 1
VL PVC large coaxial, general purpose, water resistant, flexible -10 to 105 3.1 500 2
NL PTFE flat 2 core, good mechanical strength and flexibility. Resistant to oils, acids, adverse agents and fluids. -75 to 250 (Intermittently to 300) 2.3 x 1.3 50
NS PFA 2 core, ultra thin. Resistant to oils, acids, adverse agents and fluids. -75 to 200 1.3 x 0.6 15
MT PTFE 2 core (twisted 7/.2), good mechanical strength and flexibility. Resistant to oils, acids, adverse agents and fluids. -50 to 250 2.0 15
FG High temperature fibreglass, flat pair. Max 400 3.0 50

1. Lead length up to 20m can be supplied with thermistor sensors.

2. For platinum resistance types P2 max length is 15m.

Connector types

Code 0 No plug (bare wire tails).
Code 3 Thermoplug (colour coded) 2 pin ISO.
T type - Brown
K type - Green
J type - Black
Note: Thermocouple plugs are not included with either Eltek data loggers or GenII GS21/24 or 24H transmitters.
Code 4 Tini QG-3 pin

For transmitters

Code 5
Code 6
Code 7
Mini plug 2 way with strain relief (3.4mm pin spacing)
Mini plug 4 way with strain relief
Mini plug 8 way with strain relief

For wired loggers

Code 8
Code 9
Code 10
Code 11
Code 12
Code 13
Standard plug 3 way with strain relief (5.3mm pin spacing)
Standard plug 4 way with strain relief
Standard plug 5 way with strain relief
Standard plug 7 way with strain relief
Standard plug 8 way with strain relief
Standard plug 10 way with strain relief

For PT100 Sensors, contact Eltek for advice on connector types.

Note: Eltek can terminate probes with other connectors to mate with the Squirrel when ordered together with the data logger.

Spare probes are supplied only terminated with the connector types identified above.

Ordering

The temperature probe ordering code is as follows:

EL [Probe]-[Sensor]-[Lead]-[Lead Length]-[Connector]

For example, to order a general purpose CS U Thermistor probe with 3m of PVC large coaxial lead and a 2 way mini plug with strain relief, the order code would be ELCS-U-VL-03-5.

Choose the probe configuration you require from the Probe Types, Cables and Connectors sections and build an order code like the one above. Please ensure the order code is valid, i.e. that the cable type that you may have specified is compatible with the sensor, plug and range that you require.