Existing 3 Phase 3 Wire 277/480V distribution board feed 3 Phase 4 Wire Devices

[David Christian]

Hi Guys,

I have one lab TI project that some of lab equipment are 480V, 3 phase 4 wires.

But based on as-built panel schedules, there are only 3 Phase 3 Wire 277/480V distribution boards available.

I checked the wiring diagram of most of the lab equipment and it needs neutral as well.

Is there any solution to address this issue?

When I checked the as-built panel schedules. I found that most of 480V lab equipment are fed by 3 phase 3 wire 277/480V distribution boards. That might be wrong, but these lab equipment have already been installed on site. Is there any better solution?

My client might not want to install a new panel, I have to use 100Amps 277/480V lighting panel to feed some small 480V lab equipment. For big lab equipment, I have to use spare breakers in the main switchboard.


I appreciate any suggestions.

David

 

[infinity]

Since you only have 3Ø, 3 wire, 480 volts you'll need a transformer to create a neutral and get 3Ø, 480Y/277 volts.

 

[David Christian]

Since you only have 3Ø, 3 wire, 480 volts you'll need a transformer to create a neutral and get 3Ø, 480Y/277 volts.

Thanks for your suggestion. Yeah, it would better to provide a transformer to get neutral.

 

[Little Bill]

If you currently have 277V, you already have a neutral.

 

[Little Bill]

Duplicate, see here

3 Phase 3 Wire panel feed 3 phase 4 wire lab equipment

Hi Guys, I have one project that I find some lab equipment are fed by 3 phase 3 wire panel. Please see the picture below. I checked the old wiring diagram of each lab equipment. It shows that the equipment needs neutral. Therefore, I just want to double check whether it is fine to use 3 phase 3...

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