Reading on the Single phase 208 from 3 phase panels

[KnobnTube]

I was reading the thread below:
http://forums.mikeholt.com/showthread.php?t=167941&highlight=single+phase+208Y+panel

What panel does one use for the application on the single phase 208?

Looking at manufacturers, they have their ratings very explicit on panelboards.

Example:
3 phase panels specifiy they can be used for either of the 208 or 240 application.
Schneider Electric Load Center, 125 A - Panel Boards - QO312L125G
Voltage Rating 208Y/120 Vac - 240/120 Vac Delta - 240 Vac Delta

Single phase, however is explicit for only 240 volt.
SCHNEIDER ELECTRIC QO120M100
Voltage Rating 120/240 Vac


So, how does one use the standard 120/240 for a single phase 208 application when the manufacturer does not provide the rating in the instructions/specifications?


Just curious here, I understand 240 volt rated is higher than 208, but then why do they specify the 2 with 3 phases, it would have no meaning.

So there has to be a reason for the single phase panels not to be dual rated?

Thanks

 

[infinity]

Great question, not sure why that is but will the 1?, 120/240volt panel operate any differently on a 208Y/120 volt system?

 

[kwired]

I was reading the thread below:
http://forums.mikeholt.com/showthread.php?t=167941&highlight=single+phase+208Y+panel

What panel does one use for the application on the single phase 208?

Looking at manufacturers, they have their ratings very explicit on panelboards.

Example:
3 phase panels specifiy they can be used for either of the 208 or 240 application.
Schneider Electric Load Center, 125 A - Panel Boards - QO312L125G
Voltage Rating 208Y/120 Vac - 240/120 Vac Delta - 240 Vac Delta

Single phase, however is explicit for only 240 volt.
SCHNEIDER ELECTRIC QO120M100
Voltage Rating 120/240 Vac


So, how does one use the standard 120/240 for a single phase 208 application when the manufacturer does not provide the rating in the instructions/specifications?


Just curious here, I understand 240 volt rated is higher than 208, but then why do they specify the 2 with 3 phases, it would have no meaning.

So there has to be a reason for the single phase panels not to be dual rated?

Thanks

Good question. AFAIK though you can supply any of those panels with any voltage system that doesn't exceed maximum (nominal) voltage ratings. You could also supply a 600 volts rated panel and breakers with only 240/120 or 208/120. Usually is less cost to use lower volt rated gear but nothing wrong otherwise.

You will see SCCR/AIR differences on breakers and panel bus for different system applications, but mostly in the commercial panelboards and not in the "loadcenter" category products.

 

[jim dungar]

Single phase, however is explicit for only 240 volt.
SCHNEIDER ELECTRIC QO120M100
Voltage Rating 120/240 Vac

No it is not.

This panel is listed for a maximum nominal voltage Line to Ground of 120V and a maximum nominal voltage Line to Line of 240V.
You need to look into the labeling requirements of the equipment and not go off of industry slang. "Distribution equipment", and protective devices, are listed with maximum voltages, therefore they are acceptable for use on lower voltages.

 

[xformer]

I was reading the thread below:
http://forums.mikeholt.com/showthread.php?t=167941&highlight=single+phase+208Y+panel

What panel does one use for the application on the single phase 208?

Looking at manufacturers, they have their ratings very explicit on panelboards.

Example:
3 phase panels specifiy they can be used for either of the 208 or 240 application.
Schneider Electric Load Center, 125 A - Panel Boards - QO312L125G
Voltage Rating 208Y/120 Vac - 240/120 Vac Delta - 240 Vac Delta

Single phase, however is explicit for only 240 volt.
SCHNEIDER ELECTRIC QO120M100
Voltage Rating 120/240 Vac


So, how does one use the standard 120/240 for a single phase 208 application when the manufacturer does not provide the rating in the instructions/specifications?


Just curious here, I understand 240 volt rated is higher than 208, but then why do they specify the 2 with 3 phases, it would have no meaning.

So there has to be a reason for the single phase panels not to be dual rated?

Thanks

Its not a standard... Its a rating. Panels can be used on circuits rated up to 240 Volts.

 

[KnobnTube]

Okie Dokie

Okie Dokie

Lets look at WHY the manufacturer is EXPLICIT in their labeling please, not the rambling.

Now, Square D states on their 3 phase PANELS they are listed for 120/208Y AND 120/240 !

So, why? Why not 120/240 volt 3 phase if it is ONLY about the voltage rating.

I have sent in a request to Square D engineering through my distributors to see if there is a reason behind all this or not.

With that said, how may times have you installed a 14-50R instead of am 18-50R on a 120/208 system?

 

[ActionDave]

Lets look at WHY the manufacturer is EXPLICIT in their labeling please, not the rambling.

Now, Square D states on their 3 phase PANELS they are listed for 120/208Y AND 120/240 !

That what's available in the US.

So, why? Why not 120/240 volt 3 phase if it is ONLY about the voltage rating.

There's a lot of hand wringing worriers in the US. The ones that play it right end up in a office somewhere.

I have sent in a request to Square D engineering through my distributors to see if there is a reason behind all this or not.

With that said, how may times have you installed a 14-50R instead of am 18-50R on a 120/208 system?

I would not install an 18-50R on a 240V system.

 

[kwired]

Lets look at WHY the manufacturer is EXPLICIT in their labeling please, not the rambling.

Now, Square D states on their 3 phase PANELS they are listed for 120/208Y AND 120/240 !

So, why? Why not 120/240 volt 3 phase if it is ONLY about the voltage rating.

I have sent in a request to Square D engineering through my distributors to see if there is a reason behind all this or not.

With that said, how may times have you installed a 14-50R instead of am 18-50R on a 120/208 system?

I'd almost bet there isn't a single appliance store/installer in existence that would ever have a power supply cord for the range with a 18-50 cord cap, or for that matter ever even heard of such an item. I can say I am aware there is a standard for them - but pretty certain I have never seen one either.

 

[jim dungar]

Lets look at WHY the manufacturer is EXPLICIT in their labeling please, not the rambling.

I am not rambling.

This is from Schneider Electric' FAQs
http://www.schneider-electric.us/sites/us/en/support/faq/faq_main.page

Can a 1ph QO load center be use on a 120/208v, 1ph-3w system?
Yes. However, only two of the three phases will be connected to the lugs of the load center.

Is the H328NR service entrance rated when being used at 120/208v?
This device can be used as Service Entrance Equipment when being used at a maximum of 240v.

 

[tx2step]

I am not rambling.

This is from Schneider Electric' FAQs
http://www.schneider-electric.us/sites/us/en/support/faq/faq_main.page

Can a 1ph QO load center be use on a 120/208v, 1ph-3w system?
Yes. However, only two of the three phases will be connected to the lugs of the load center.

Is the H328NR service entrance rated when being used at 120/208v?
This device can be used as Service Entrance Equipment when being used at a maximum of 240v.

:happyyes::thumbsup: