Equipment Voltage Ratings

[buddy91082]

Equipment such as switchboards and panel boards have a nameplate voltage rating. Is there an allowable utilization voltage fluctuation above equipment nameplate rating?

Example would be a panel low voltage panel board is rated 208v. If I need to increase voltage on the transformer serving the panel via tap changers to compensate for voltage drop, is there a maximum voltage increase that the panel can see above it's rating? If so, what is the reference document?

Thanks.
b

 

[magoo2]

The panel is probably rated 240 V.

In any event, the reference document I would suggest would be ANSI C84.1-2011. You can download a copy for free.

 

[buddy91082]

Thanks. What if the panel is rated 240v and I need to increase voltage 5% for voltage drop to 252v?

 

[magoo2]

120/240 V is a typical nominal voltage ratings of some service panels for residential and small commercial installations. The electric utility is permitted to deliver plus and minus 5% from the nominal rating so 252 V would be OK for a 240 V panel.