SQD NF Panelboards breakers w/Aux contacts

[PanelGuy1315]

Hello All,

I have a question about the SqD NF style panelboards. We require the breakers that come with the Aux contact built-in but they take up a 4th pole on the board. This means when we install multiple of these breakers next to each other, the phasing will be different. First breaker will be A-B-C, but the second will be B-C-A. Is this common to do?

My electrician is trying to space the breakers apart so that each one is A-B-C, but this is wasting some breaker space that we had reserved for future loads.

This panelboard is feeding control panels with DC power supplies and field mounted VFDs.

 

[don_resqcapt19]

There is no requirement to have A phase be the top pole on a 3 phase breaker. You have the same issue where there is a mix of 2 and 3 pole breakers, or even a mix of 1, 2, or 3 pole breakers.
You typically fill the spaces in order...unless you are installing single pole breakers in a high leg panel.

 

[MTW]

This panelboard is feeding control panels with DC power supplies and field mounted VFDs.

With rectified loads, what advantage is there to keeping the phase order the same?

 

[PanelGuy1315]

I think the thought is that maintenance could be confused by phasing being inconsistent across multiple breakers. I don't think the loads will care.

The sequencing of the phases wouldn't change A->B->C->

 

[PanelGuy1315]

There is no requirement to have A phase be the top pole on a 3 phase breaker. You have the same issue where there is a mix of 2 and 3 pole breakers, or even a mix of 1, 2, or 3 pole breakers.
You typically fill the spaces in order...unless you are installing single pole breakers in a high leg panel.

Thanks for this reply. That makes sense. I hadn't thought about a mix.