Spectrum Controls 1769 Series User Manual page 18

6 channel isolated thermocouple/mv input module
Hide thumbs Also See for 1769 Series:
Table of Contents

Advertisement

2-4
Compact™ IO Isolated Thermocouple Module
User's Manual Pub. 0300244-01 Rev. A
Follow the guidelines below when wiring the module.
General
Power and input wiring must be in accordance with Class 1, Division 2 wiring
methods, Article 501-4(b) of the National Electric Code, NFPA 70, and in
accordance with the authority having jurisdiction.
Channels are isolated from one another by 500V dc maximum.
Route field wiring away from any other wiring and keep it as far as possible
from sources of electrical noise, such as motors, transformers, contactors, and ac
devices. As a general rule, allow at least 15.2 cm (6 in.) of separation for every
120V of power.
Routing field wiring in a grounded conduit can reduce electrical noise.
If field wiring must cross ac or power cables, ensure that they cross at right
angles.
If multiple power supplies are used with analog millivolt inputs, the power
supply commons must be connected.
Terminal Block
Do not use the module's NC terminals as connection points.
Do not tamper with or remove the CJC sensors on the terminal block. Removal
of either one or both sensors will reduce accuracy.
For millivolt sensors, use Belden 8761 shielded twisted-pair wire (or equivalent)
to ensure proper operation and high immunity to electrical noise.
For a thermocouple, use the shielded, twisted-pair thermocouple extension lead
wires specified by the thermocouple manufacturer. Using the incorrect type of
thermocouple extension wire or not following the correct polarity will cause
invalid readings.
To ensure optimum accuracy, limit overall cable impedance by keeping a cable
as short as possible. Locate the module as close to input devices as the
application permits.
Grounding
The possibility exists that a grounded or exposed thermocouple can
!
become shorted to a potential greater than that of the thermocouple
itself. Due to possible shock hazard, take care when wiring grounded or
Attention
exposed thermocouples. See Appendix B, Using Thermocouple
Junctions.
This product is intended to be mounted to a well-grounded mounting surface
such as a metal panel. Additional grounding connections from the module's
mounting tabs or DIN rail (if used) are not required unless the mounting surface
cannot be grounded.
Keep cable shield connections to ground as short as possible.

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the 1769 Series and is the answer not in the manual?

Subscribe to Our Youtube Channel

This manual is also suitable for:

1769sc-it6i

Table of Contents