Proper use of a non grounding plug

[reyamkram]

I was repairing a plug the other day and I noticed it was a HBL 3431 non grounding type plug. It was being used on a grounded system, 240 volt high leg delta. It has 3 hot and a ground. My question is.....Is it right to use a non grounding plug on that type of system? The NEC says to use listing and labeling material. If I am not mistaking that HBL 3431 non grounding plug would not be listed or labeled for that use. The one terminal on that plug, the silver one ....would it be rated to handle a ground fault current? The grounding conductor is connected to the silver terminal of the plug and if I am not mistaking I don't believe that would be correct. Any input or advice on the subject would be appreciated.

 

[petersonra]

I was repairing a plug the other day and I noticed it was a HBL 3431 non grounding type plug. It was being used on a grounded system, 240 volt high leg delta. It has 3 hot and a ground. My question is.....Is it right to use a non grounding plug on that type of system? The NEC says to use listing and labeling material. If I am not mistaking that HBL 3431 non grounding plug would not be listed or labeled for that use. The one terminal on that plug, the silver one ....would it be rated to handle a ground fault current? The grounding conductor is connected to the silver terminal of the plug and if I am not mistaking I don't believe that would be correct. Any input or advice on the subject would be appreciated.

The data sheet indicates that plug is intended to be used on 208V 3 phase systems.

https://hubbellcdn.com/specsheet/WIRING_HBL3431C_spec.pdf

I am moderately surprised UL would list a plug that does not have provision for an EGC.

I would not be real worried about the fault current. All of the terminals would need to be able to handle whatever ground fault current there is.