A-B 1746-NT4 General Description SLC™ 500 4-Channel Thermocouple/mV Input Module

General Description

The thermocouple/mV module receives and stores digitally converted

thermocouple and/or millivolt (mV) analog data into its image table

for retrieval by all fixed and modular SLC 500 processors. The module

supports connections from any combination of up to four

thermocouple or mV analog sensors.

The following tables define thermocouple types and their associated

full scale temperature ranges and also list the millivolt analog input

signal ranges that each 1746-NT4 channel will support. To determine

the practical temperature range your thermocouple supports, refer to

the specifications in Appendix A.

Each input channel is individually configurable for a specific input

device and provides open-circuit, over-range, and under-range

detection and indication.

Hardware Features

The thermocouple module fits into any single-slot, except the

processor slot (0), in either an SLC 500 modular system or an SLC 500

fixed system expansion chassis (1746-A2). It is a Class 1 module (uses

8 input words and 8 output words). It interfaces to thermocouple

types J, K, T, E, R, S, B, and N, and supports direct ±50 mV and ±100

mV analog input signals.

The module requires the use of Block Transfer in a remote configuration.

The module contains a removable terminal block providing

connection for four thermocouple and/or analog input devices. There

are also two, cold-junction compensation (CJC) sensors used to

compensate for offset voltages introduced into the input signal as a

result of the cold-junction, i.e., where the thermocouple wires connect

to the module wiring terminal. There are no output channels on the

module. Module configuration is done via the user program. There are

no DIP switches.