Why might I get an NST on my ATV320 when I wire a relay to the digital output (DQ)?

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Issue:
Getting NST on my ATV320 when wiring a relay to the digital output (DQ).

Product Line:
Altivar 320

Environment:
All

Cause:
NST on the ATV320 with relay connected

Resolution:
1. Check to make sure your relay is wired correctly in series with the digital output:

Jumper +24V to DQ+
Wire your + side of your relay coil to DQ-
Wire the other side of the coil to COM

2. Measure the amperage pull of your relay. The digital output and the drive's +24V supply each have a maximum 100mA capacity.

If your relay is pulling more than 100mA, it's pulling down the +24V in the drive and causing the NST.
See attachment.