KarlS
Member
- Location
- Houston, TX
I currently have a panelboard rated 480/277V, 4W. The panel is equiped with 480/277V slash rated breakers. This panel is feed by a 480V Wye transformer that is high impedance grounded. I do not have a neutral running from the transformer into the equipment. All the breakers are 3phase for 3ph loads. I have a UL inspector who insists this must be a 480, 3W panel per 240.85. This article as I read it, refers to Delta confirgurations where the voltage can exceed the slash rated breaker. I think the inspectors hang up is the article mentions slash rated 480/277V is permitted to be applied in a solidly grounded circuit.
The panel and breakers are slash rated but I am running 3ph, 480V to the panel with no neutral. I don't see how the inspector is confusing this. Do you see any issues with using a slash rated panel and breakers in this application? Since I know this will come up the fault current rating is 65KAIC. I am fine in that respect.
The panel and breakers are slash rated but I am running 3ph, 480V to the panel with no neutral. I don't see how the inspector is confusing this. Do you see any issues with using a slash rated panel and breakers in this application? Since I know this will come up the fault current rating is 65KAIC. I am fine in that respect.