Omron CK3M Seres Hardware User Manual page 177

 Controller Ground Terminals
The Controller has the following ground terminal.
Grounding
type
Functional
Grounding
When the functional ground terminal is correctly grounded, it is generally effective in suppressing
power supply common noise. Occasionally, however, grounding this terminal will result in picking
up more noise, so be careful when using it.
CK3M/CK5M Series Programmable Multi-Axis Controller Hardware User's Manual (O036)
Symbol
Ground this terminal when power supply noise causes malfunc-
tioning.
Connection
4 Installation
4
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