Cutler-Hammer D320 PLC, User Manual

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D320 PLC User's Manual
Filters
Filters should be used to suppress high frequency noise.
When using a low-pass filter specify one that is designed for power line applications. Many different
types are available from simple modules to complex units.
A single device is not necessarily the most cost-effective device for all applications. In specifying the
proper filter one must take into account the amplitude/power level of the noise and how often the noise
is present.
When the proper device is selected it is best to place the device as close to the PLC power supply
connections as possible. Below is an example of how to install a filter. The chart lists a typical
midrange power line filter for reference.
For installation and application details, refer to the manufacturers manuals.
Model Name Manufacturer Remarks
PQI-3120N12 Superior Electric, DANA/
Warner Electric Division Used for 120 V power
PQI-3220N12
Superior Electric, DANA/
Warner Electric Division
Used for 240 V power
The PQI-3120N12 and PQI-3220N12 come in a NEMA 12 rated enclosure.
AC input
Ground
terminal
Triple ground (Less than 100
Ω
of ground resistance)
Filter
PLC
AC power