Honeywell CN100 Planning And Installation Manual page 29

Connect CN100 Controller to earth ground through power input
terminal chassis ground pin (pin 33) as illustrated in the following
figure.
Figure 4-5: Redundant Controller Grounding
Grounding and Shielding recommendations:
Use individually shielded twisted pair of cables with full foil shield
n
coverage, to minimize crosstalk within the cable bundle.
Select appropriate wires for pulse counting performance. The foil
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along with the overall braid provides effective shielding.
Low capacitance enables fast counting, ensuring that the pulse
n
fidelity (pulse distortion) for longer cable lengths is not
compromised.
Use cables that have a braided shield (55% or greater coverage)
n
for best EMI/RFI performance. Double shielded cable with a braid
over foil performs best, if the environment is EMI harsh. Proper
grounding of the shields is necessary to obtain the optimum
performance.
The shields (screen) of the cable carrying the pulse signals can be
n
grounded at any one or both ends (double termination). If the site
has problem with low frequency ground loops, ground the shield
at one end to minimize common mode noise and interference.
Wire Conductor Size
See the following table for input wire conductor size range for each of
the ports and connectors:
Chapter 4 - CN100 Platform Installation
29