480 Volt Bus Bar

[joec]

I'm looking into whether or not additional battery chargers can be installed connected to a 480 volt, 3 phase bus bar in an industrial application. The bus bar is supplied from a 225A breaker in a distribution panel. There are currently 23 chargers powered through individual disconnects. I'm assumimg an engineer determined that all chargers would not be loaded simultaneously. I don't like assuming! The chargers run over three hours so I believe they would be considered continuous loads. My questions are: 1) Is this a code compliant installation as it is? and 2) How can I determine how many, if any, chargers I can add to the installation?

 

[steve66]

Re: 480 Volt Bus Bar

You didn't post the load each charger draws, but I would guess that each charger would draw full load for only a short time when the battery is first connected. Most battery chargers I have seen (I am assuming industrial chargers would be the same) drop the current as they charge.

Thus, I wouldn't call them continuous loads.

Steve

 

[joec]

Re: 480 Volt Bus Bar

Thanks Steve. Pretty ignorant to leave out charger current rating. They are rated at 15 amps each, internally fused. I understand the charger current load drops off as the batteries charge. I'm going to record current on the bus for a at least week to find out what the peak current draw is. I would like to find the right way to figure this out though.