Grounding DC2

[chris kennedy]

Yesterday I was doing some trouble shooting in a UL 508A cabinet. I was texting back and forth with the OEM engineer when he asked me to ground DC2(-) of the power supply.
This didn't make any difference in the outcome of the problem but I found it an odd request.
To me the idea of possibly introducing any noise or transients on the EGC into the DC side of a power supply seems like a bad idea.

Has anyone seen this before?

Thanks

 

[jim dungar]

Has anyone seen this before?

Yes.
When I built control panels the DC power supply negative was always grounded.

 

[LarryFine]

Seems that a floating supply would risk being noisier.

 

[qcroanoke]

250.162 requires a DC ground if over 60 volts

 

[Dsg319]

Seems fine to me, I’d just have a properly sized fuse to keep from burning up the DC power supply in the even of a fault.