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J and k type thermocouple input modules -16, 10 j and k type thermocouple input modules -16, 10 j and k type thermocouple input modules – Emerson ROC827 User Manual

Page 86

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ROC827 Instruction Manual

Issued Mar-06

Input/Output Modules

4-16

Note

: All I/O modules are isolated on the field side. Be aware that you can

induce ground loops by tying commons from various modules together.

Figure 4-14. RTD Sensor Wiring Terminal Connections

Figure 4-14 and Table 4-2 display the connections at the RTD terminals
for the various RTD probes.

Table 4-2. RTD Wiring

Terminal

4-Wire RTD

3-Wire RTD

2-Wire RTD

REF

Red

Jumper to +

Jumper to +

+

Red

Red, Jumper to REF

Red, Jumper to REF

White

White

White, Jumper to RET

RET

White

White

Jumper to –

Note

: The wire colors for the RTD being used may differ.

4.10

J and K Type Thermocouple Input Modules

The five-channel J and K Type Thermocouple Input module monitors
either J or K Type Thermocouple (T/C). J and K refer to the type of
material used to make a bimetallic junction: Type J (Iron/Constantan) and
Type K (Chromel/Alumel). These dissimilar junctions in the thermocouple
junction generate different millivolt levels as a function of the heat to
which they are exposed.

The J and K Type Thermocouple Input module measures the voltage of
the thermocouple to which it is connected. The T/C voltage is measured
and a Cold Junction Compensation (CJC) correction factor is applied to
compensate for errors due to any voltage inducted at the wiring terminals

Jumper

4-Wire RTD

3-Wire RTD

2-Wire RTD

Red

Red

Red

Jumper

Red

Jumper