I am just trying to know more about the product, why a panel originally labeled at 208V 3ph 4w would not work at 240V, 3ph 4w. All the breakers are 240V and main is 600V. I am struggling to get feedback from manufacturer. I understand that there might be a certification issue, but technically what would make it not suitable for 240V?
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Eaton Panel PRL 1A 2
- Thread starter tinotoro
- Start date
- Moderator
- #2
240V, 3ph 4w ???
240V, 3ph 4W would be 240/139V.
That is not a standard voltage in North America.
The only time that I have seen that voltage has been onboard ship where a ship's engineer who didn't understand three phase voltages saw 208 Volts on a voltmeter and cranked the AVR up to 240 Volts.
With 139 Volts instead of 120 Volts on the lighting circuits, they changed a lot of light bulbs.
On the other hand, this appears to be a custom build as a "Car Charger Panel.
As such it may not be suitable for use on a 120/240 V wild leg system.
The information label showing 120/208 Volts is an information label, not an approvals label.
While the panel may not be suitable as a Car Charger Panel on a wild leg system, if you are going to repurpose it for another use on a wild leg system, just run a Sharpy over the part where it says 120/208V.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
240V, 3ph 4W would be 240/139V.
That is not a standard voltage in North America.
The only time that I have seen that voltage has been onboard ship where a ship's engineer who didn't understand three phase voltages saw 208 Volts on a voltmeter and cranked the AVR up to 240 Volts.
With 139 Volts instead of 120 Volts on the lighting circuits, they changed a lot of light bulbs.
On the other hand, this appears to be a custom build as a "Car Charger Panel.
As such it may not be suitable for use on a 120/240 V wild leg system.
The information label showing 120/208 Volts is an information label, not an approvals label.
While the panel may not be suitable as a Car Charger Panel on a wild leg system, if you are going to repurpose it for another use on a wild leg system, just run a Sharpy over the part where it says 120/208V.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
".. why a panel originally labeled at 208V 3ph 4w would not work at 240V, 3ph 4w. All the breakers are 240V and main is 600V. ... I understand that there might be a certification issue, but technically what would make it not suitable for 240V?.."
I have the following opinion for your consideration.
1. Based on the attached file, the power source is ABC + N. Where loads are connected between AN, BN, CN ..at 120V.
2. The board was originally designed for 120/208V 4W . It should be fine for connection to 139/240V 4W , with breakers connected to AN, BN, CN.. at 139V.
3. It does not matter what is the name of the board. Technically, it is safe for a board designed for 120/208V 4W to operate on 139/240V 4W source. Certification or marking approval is a separate issue.
Che Kuan Yau (Singapore)
I have the following opinion for your consideration.
1. Based on the attached file, the power source is ABC + N. Where loads are connected between AN, BN, CN ..at 120V.
2. The board was originally designed for 120/208V 4W . It should be fine for connection to 139/240V 4W , with breakers connected to AN, BN, CN.. at 139V.
3. It does not matter what is the name of the board. Technically, it is safe for a board designed for 120/208V 4W to operate on 139/240V 4W source. Certification or marking approval is a separate issue.
Che Kuan Yau (Singapore)
- Moderator
- #4
What system voltage do you intend to use the panel on?
There must be another rating label somewhere on the panel.
120/240V "Wild Leg" three phase is quite rare in Western Canada.
139/240V three phase is only seen when someone sets a generator voltage wrong.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
There must be another rating label somewhere on the panel.
120/240V "Wild Leg" three phase is quite rare in Western Canada.
139/240V three phase is only seen when someone sets a generator voltage wrong.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
I have the following opinion for your consideration.
1. "...The board was originally designed for 120/208V 4W ... Technically, it is safe to operate on 139/240V 4W source..."
2. " Technically " include Voltage and current ratings, Mechanical dimension on creepage and clearance distances, Insulation resistance test voltage, Impulse voltage rating and temperature rise etc..
Che Kuan Yau (Singapore)
1. "...The board was originally designed for 120/208V 4W ... Technically, it is safe to operate on 139/240V 4W source..."
2. " Technically " include Voltage and current ratings, Mechanical dimension on creepage and clearance distances, Insulation resistance test voltage, Impulse voltage rating and temperature rise etc..
Che Kuan Yau (Singapore)
I have to add the following, which was inadvertently omitted.
1. "...The board was originally designed for 120/208V 4W ... Technically, it is safe to operate on 139/240V 4W source..."
2. " Technically " ... include also Dielectric voltage test and duration.
Che Kuan Yau (Singapore)
1. "...The board was originally designed for 120/208V 4W ... Technically, it is safe to operate on 139/240V 4W source..."
2. " Technically " ... include also Dielectric voltage test and duration.
Che Kuan Yau (Singapore)
- Moderator
- #7
The main breaker is rated for 600 VAC and 250 VDC.
The breaker panel will have a similar rating plate.
However, the rated voltage of the panel may be 300 VAC or 600 VAC, the two common rating classes in Canada.
If you intend to use this panel on 120-240/240VAC 3 ph, any accessories in the panel must be evaluated for suitability for a wild leg voltage of 208 VAC to neutral/ground.
In Canada, equipment is rated for use at either 300 VAC or 600 VAC.
The main breaker and the basic panel should be suitable for use at 240 Volts.
However, this is a purpose built panel and you have not told us if there are any accessories in the panel.
For example;
Some phase loss relays and phase reversal relays depend on a neutral connection and may not operate properly on a wild leg system.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
The breaker panel will have a similar rating plate.
However, the rated voltage of the panel may be 300 VAC or 600 VAC, the two common rating classes in Canada.
If you intend to use this panel on 120-240/240VAC 3 ph, any accessories in the panel must be evaluated for suitability for a wild leg voltage of 208 VAC to neutral/ground.
In Canada, equipment is rated for use at either 300 VAC or 600 VAC.
The main breaker and the basic panel should be suitable for use at 240 Volts.
However, this is a purpose built panel and you have not told us if there are any accessories in the panel.
For example;
Some phase loss relays and phase reversal relays depend on a neutral connection and may not operate properly on a wild leg system.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!
-
2
- #8
The usual reason is that if you want to use a 240/120V 3ph 4w Delta panel, any 2 pole BREAKERS that fit in it must be "straight 240V" rated, because there is a possibility that they can plug/bolt onto the B phase, where the maximum L-G reference is HIGHER than 120V. Therefore a panel that is designed for 240/120V 3ph 4w Delta systems is often designed with physical restrictions as to what type of branch breakers can be installed.
Most "standard" 2 pole breakers are rated 120/240V, meaning they NEVER see a L-G reference higher than 120V. So because, in a panel MADE for 208Y120V 3ph 4w, the L-G will never be more than 120V, they can use ANY breaker in the branch section. But if you were to then use it on 240/120V 3ph 4w Delta, the inappropriate branch breakers CAN fit in there, allowing for a potentially dangerous situation. So you CANNOT use a panel BUILT AS 208Y120V for a 240/120V 3 Ph 4W application.
You CAN by the way, go the other way. If you HAVE a panel BUILT for 240/120V 3ph 4w Delta, and you want to use it for 208Y120 3ph 4 w, that is OK.
" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
Most "standard" 2 pole breakers are rated 120/240V, meaning they NEVER see a L-G reference higher than 120V. So because, in a panel MADE for 208Y120V 3ph 4w, the L-G will never be more than 120V, they can use ANY breaker in the branch section. But if you were to then use it on 240/120V 3ph 4w Delta, the inappropriate branch breakers CAN fit in there, allowing for a potentially dangerous situation. So you CANNOT use a panel BUILT AS 208Y120V for a 240/120V 3 Ph 4W application.
You CAN by the way, go the other way. If you HAVE a panel BUILT for 240/120V 3ph 4w Delta, and you want to use it for 208Y120 3ph 4 w, that is OK.
" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
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