Omega

Sensor Input Wiring Sensor Wiring Notes

For safety and best controller performance,

Sensor leads (thermocouple and RTD) should not be run in the same conduit as power wiring.

Twisted pair, shielded wire is recommended for sensor connections.

False temperature readings can occur if the sensor wire is exposed to electrical noise.

Ungrounded thermocouples are recommended.

Thermocouple extension wire, if required, must be the same type as the thermocouple (i.e. if a Type K thermocouple is used, then Type K extension wire must be used.)

Shielded thermocouple wire, if used, must have the shield grounded at one end only, preferably at the shield ground terminal on the controller as shown in Figure 3.6.

Three-wire RTDs are recommended for greatest accuracy.

Standard shielded copper wire is recommended for RTD extensions.

Thermocouple Inputs

It is important to observe polarity (+,-) when connecting thermocouple leadwires. ANSI color coding for the thermocouples used with this instrument are

Thermocouple

 

 

Type

Material

Polarity (+)

Polarity (-)

 

 

 

 

J

iron/constantan

white

red

K

chromel/alumel

yellow

red

Make thermocouple wiring connections to terminals as shown in Figure 3.6.

TC +

TC -

Shield Ground

Figure 3.6

Thermocouple Connections with Shield

CN 2110

8

Section 3–Installation and Wiring

Page 12
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Chromalox CN2110 manual Sensor Input Wiring Sensor Wiring Notes, Thermocouple Inputs