Panel replacement 240volt delta

Status
Not open for further replies.
Dsg319

Dsg319

Senior Member
Location
West Virginia
Occupation
Wv Master “lectrician”
Is it acceptable to use a 208y/120 3ph 4w panel for a 3ph 4w 240volt delta feeder?

Replacing an old Federal Pacific panel, and can get the 208y 3ph panel much quicker.
 
The only thing I can see is possible violation of the manufacture listing. But from a safety and electrical theory stand point. What are the issues?
 
Dsg319 said:
The only thing I can see is possible violation of the manufacture listing. But from a safety and electrical theory stand point. What are the issues?
Click to expand...
IIRC, Siemens "true panel boards" do have a specific letter in the part number which indicates the system type and it is different for 120/208 vs 120/240 three phase, however I doubt there is actually anything different. For load centers, I'll bet a a Reuben sandwich they say they are fine with 120/240 delta.
 
I cant speak definitively for other brands, but Siemens 3 phase load centers are fine with 120/240 three phase. Here's a screenshot from the catalog page. Again, don't forget you would need fully rated breakers that are connected to the high leg.
 

Attachments

  • Screenshot_20210911-070132.png
    Screenshot_20210911-070132.png
    476.1 KB · Views: 20
Most have 120/208 in the panel voltage nameplate, the delta rated panels have 120/240 on them. Different panel? Probably not. But if you have a sharp inspector, he will kick you on it.
 
electrofelon said:
Can someone find a load center that is rated for 120/208 three phase but not 120/240 three phase?
Click to expand...

I just glanced through the Eaton catalog…. On CH and BR 3-phase loadcenters it says “208Y/120v or 240v”.

The Square D catalog says the same thing for QO loadcenters


Sent from my iPhone using Tapatalk
 
I haven't installed a GE loadcenter in over 20 years but just looked online.

PowerMark Plus Three Phase Load Centers Three Phase, Four Wire, 208Y/120Vac1
1 Also UL Listed for three phase, four-wire 240/120 Volts Hi Leg delta and three phase, three-wire 240 Volts (240V breakers must be installed).
 
curt swartz said:
I haven't installed a GE loadcenter in over 20 years but just looked online.

PowerMark Plus Three Phase Load Centers Three Phase, Four Wire, 208Y/120Vac1
1 Also UL Listed for three phase, four-wire 240/120 Volts Hi Leg delta and three phase, three-wire 240 Volts (240V breakers must be installed).
Click to expand...
Awesome👍
 
curt swartz said:
I haven't installed a GE loadcenter in over 20 years but just looked online.

PowerMark Plus Three Phase Load Centers Three Phase, Four Wire, 208Y/120Vac1
1 Also UL Listed for three phase, four-wire 240/120 Volts Hi Leg delta and three phase, three-wire 240 Volts (240V breakers must be installed).
Click to expand...
Doesn't that mostly come down to - don't install 120/240 rated breakers on the high leg?

You won't be attaching 120 volt loads to the high leg anyway so not a problem there.

AFAIK all the three pole breakers are straight 240 volt rated - so no problem there.

It comes down to if you attach a two pole breaker (for say a 240 volt single phase load) to the high leg you will need a not so commonly stocked 2 pole 240 volt breaker. All the commonly stocked ones are 120/240 rated.
 
Where I had a problem with this was when ordering a NQ panelboard one time I told my salesman it will be a high leg system, more like I think he asked me. The problem wasn't the rating of the panel but other details of the order. I needed three phase feed through lugs but didn't have any three pole branch breakers on the order - so they specially made me (didn't know why it was taking so long) a panelboard with all three phase buses but only with branch connections to A and C - so there was no three phase available for branch breakers. I did need some three phase branches, just happened to already have the breakers and didn't order any. Once we straightened this out the replacement came from stock items and had it right away.

Same basic panel is rated for 208/120 or for 120/240 with high leg.

Loadcenters (Square D anyway) are also rated for either.

As mentioned you can't connect on a "slash rated" breaker to the high leg bus in situations where you have a high leg.
 
electrofelon said:
Can someone find a load center that is rated for 120/208 three phase but not 120/240 three phase?
Click to expand...
What’s strange, is panelboards are not. Finally got over to the warehouse, and looked one up. One is rated for 120/240 delta, other is rated for 120/208. We very seldom use loadcenters in commercial.
 

Attachments

  • CE1DCE67-9412-4533-864C-40F7E02AC27D.jpeg
    CE1DCE67-9412-4533-864C-40F7E02AC27D.jpeg
    75.2 KB · Views: 12
  • 7D0FE299-8B7A-42E6-A220-BC2481629428.jpeg
    7D0FE299-8B7A-42E6-A220-BC2481629428.jpeg
    75 KB · Views: 12
hillbilly1 said:
What’s strange, is panelboards are not. Finally got over to the warehouse, and looked one up. One is rated for 120/240 delta, other is rated for 120/208. We very seldom use loadcenters in commercial.
Click to expand...
Weren't those ordered for specific jobs?

When you order factory assembled panelboards they mark the voltage listed on the panels schedules you submit. If you order off the shelf components they are universal.
 
curt swartz said:
Weren't those ordered for specific jobs?

When you order factory assembled panelboards they mark the voltage listed on the panels schedules you submit. If you order off the shelf components they are universal.
Click to expand...
I’ve bought them off the shelf that had only 120/208 as the maximum voltage on the label.
 
Status
Not open for further replies.
Top