Rockwell Automation 1746-NT4 SLC 500 Thermocouple/mV Input Module Installation Instructions - Manual (Page 8)

8 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Fixed Expansion Chassis Considerations
General Considerations
Most applications require installation in an industrial enclosure to reduce the effects
of electrical interference. Thermocouple inputs are highly susceptible to electrical
noises due to the small amplitudes of their signal (microvolt/°C).
Group your modules to minimize adverse effects from radiated electrical noise and
heat. Consider the following conditions when selecting a slot for the thermocouple
module. Position the module:
• in a slot away from sources of electrical noise, such as hard-contact switches,
relays, and AC motor drives
• away from modules which generate significant radiated heat, such as
32-point I/O modules
In addition, route shielded, twisted-pair thermocouple or millivolt input wiring
away from any high-voltage I/O wiring.
Terminal Block Removal
When installing the module in a chassis, it is not necessary to remove the terminal
block from the module. However, if the terminal block is removed, use the write-on
label located on the side of the terminal block to identify the module location and
type.
IMPORTANT
The 2-slot, SLC 500 fixed I/O expansion chassis (1746-A2) will
support only specific combinations of modules. If you are using
the thermocouple module in a 2-slot expansion chassis with
another SLC I/O or communication module, refer to the
SLC 500™Thermocouple/mV Input Module User Manual,
1746-6.6.1
ATTENTION
Disconnect power to the SLC before attempting to install,
remove, or wire the removable terminal wiring block.
To avoid cracking the removable terminal block, alternate the
removal of the slotted terminal block release screws.