220V Phase-Phase Same as 220V Phase-Neut

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d21x

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I have a transformer that has 220V Phase-Neut and 400V Phase-Phase.

I have a device that requires 220V. Normally I would plug this into a receptacle that is 220V Phase-Phase.

Would it be okay to plug the device into an outlet that is 220V Phase-Neut?
 
If it is a single phase device it does not matter much if it is powered L-L or L-N as long as the voltage and frequency is correct.

However, it is highly unusual in the US to see a 220V L-N circuit, so i would want to know more about the device before concluding it is Ok on your device.
 
petersonra said:
If it is a single phase device it does not matter much if it is powered L-L or L-N as long as the voltage and frequency is correct.

However, it is highly unusual in the US to see a 220V L-N circuit, so i would want to know more about the device before concluding it is Ok on your device.
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Second the motion, this needs a lot more detail.
 
petersonra said:
If it is a single phase device it does not matter much if it is powered L-L or L-N as long as the voltage and frequency is correct.

However, it is highly unusual in the US to see a 220V L-N circuit, so i would want to know more about the device before concluding it is Ok on your device.
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One familiar example is the case of the slash rated breaker. If there are similarly designed and rated components inside the equipment, it could cause problems.
 
petersonra said:
If it is a single phase device it does not matter much if it is powered L-L or L-N as long as the voltage and frequency is correct.

However, it is highly unusual in the US to see a 220V L-N circuit, so i would want to know more about the device before concluding it is Ok on your device.
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With the voltages listed in the OP 220/400 I doubt very much that this is a US application and most likely a 50hz one to boot.

But I may be wrong????
 
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hurk27 said:
With the voltages listed in the OP 220/400 I doubt very much that this is a US application and most likely a 50hz one to boot.

But I may be wrong????
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Who knows?
But if it's 400V L-L, then it would be 230V L-N for three phase.
 
I am in the USA.
A transformer on our Injection Molding Machine is 480V 3phase primary to 400V 3 phase secondary.
The device is a Ewikon Hot Runner system. It requires 220V single phase. Normally in the USA we use 220V Phase to Phase and not 220V Phase to Neutral, which is why I asked this question.
 
There are 240 volt to neutral systems in the US, kind of rare but they are out there. Around this area it is common to find either 480 volt open delta three phase systems with midpoint of one phase grounded. This results in 240 volts to neutral on two phase conductors and a high leg of about 415 volts.

There is also a lot of single phase 240/480 services around here for irrigation machines. Usually where three phase is not available and customer needs to install a phase converter to derive 480 volt three phase.

I have connected single phase 240 volt loads to such systems before. Usually with fuses for overcurrent protection - you will have the mentioned slash rated breaker issues to watch out for. The load usually doesn't care what is grounded or is not, but does care that it gets a nominal 240 volts applied to it.
 
Unbalanced Primary

Unbalanced Primary

Its the same idea of Delta High leg, where a 208v rated device can be used from wild leg to Neutral because P-P is 240v (very uncommon to do this). The only issue with both situations, and correct me if I'm wrong, is that the phase being used can have a substantially unbalanced load depending on the device.

Example:
If 208 devices where put on high leg- Neutral, instead of 240v devices P - P, the POCO would have issues.
 
Strombea said:
Its the same idea of Delta High leg, where a 208v rated device can be used from wild leg to Neutral because P-P is 240v (very uncommon to do this). The only issue with both situations, and correct me if I'm wrong, is that the phase being used can have a substantially unbalanced load depending on the device.

Example:
If 208 devices where put on high leg- Neutral, instead of 240v devices P - P, the POCO would have issues.
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Only issue with POCO would be if you put too much high leg to neutral load and overloaded the high leg transformer, and or a portion of the 120/240 transformer of an open delta system, this problem is resolved by proper sizing of transformers to meet the demands of the load and is no different then having overloaded conditions on any other system. Imbalance on POCO primary system is no different to deal with then having a large number of single phase transformers on the system - they need to alter which phase they are connected to or they will have balancing issues if they are all on same phase.
 
I think it will work

I think it will work

I have actually done this, 220v phase to neut., is common in England.In certain other countries,domestic and commercial distribution comes from a pole mounted 220 volt center tap transformer.I have used it back and forth .Must be careful though if
the source of power can handle the load capacity needed,done this for welding units, washing machines ,motors e.t.c. from the U.K..I do not see a problem.
 
d21x said:
I am in the USA.
A transformer on our Injection Molding Machine is 480V 3phase primary to 400V 3 phase secondary.
The device is a Ewikon Hot Runner system. It requires 220V single phase. Normally in the USA we use 220V Phase to Phase and not 220V Phase to Neutral, which is why I asked this question.
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You would need a 277/480 volt panel since standard breakers will not interrupt 240 volts to ground at their given AIC, plus regular panels only go to 240 not 400 volts phase to phase. Of note, yes they make straight rated breakers, however they do not come in single pole version. A 277 volt breaker will work perfectly for this.
 
mbrooke said:
You would need a 277/480 volt panel since standard breakers will not interrupt 240 volts to ground at their given AIC, plus regular panels only go to 240 not 400 volts phase to phase. Of note, yes they make straight rated breakers, however they do not come in single pole version. A 277 volt breaker will work perfectly for this.
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If only supplying one circuit it probably would cost less to use a fused safety switch as the branch circuit device, then it would be to install a 480 volt panel for just one load that needs this rating. This is assuming you are talking about single pole breaker on a high leg of a delta system.

Other option is a 2 or 3 pole non slash rated breaker and only use the one needed pole - you will need it anyway as the feeder breaker in the other scenario.
 
kwired said:
If only supplying one circuit it probably would cost less to use a fused safety switch as the branch circuit device, then it would be to install a 480 volt panel for just one load that needs this rating. This is assuming you are talking about single pole breaker on a high leg of a delta system.

Other option is a 2 or 3 pole non slash rated breaker and only use the one needed pole - you will need it anyway as the feeder breaker in the other scenario.
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For one circuit Id go that route. Out if curiosity, why don't they make a single pole 240 volt breaker?
 
mbrooke said:
For one circuit Id go that route. Out if curiosity, why don't they make a single pole 240 volt breaker?
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My guess - no demand for them. Go to Europe where they have 415/240 volt systems and I'm sure they are common as 120 volt single pole breakers are here.
 
kwired said:
If only supplying one circuit it probably would cost less to use a fused safety switch as the branch circuit device, then it would be to install a 480 volt panel for just one load that needs this rating. This is assuming you are talking about single pole breaker on a high leg of a delta system.

Other option is a 2 or 3 pole non slash rated breaker and only use the one needed pole - you will need it anyway as the feeder breaker in the other scenario.
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I think this is what my thoughts were, that is the ratings of the OCPD and pphase to ground voltages. With a 3ph system where you may have 240v to neutral available since the neutral is commonly grounded you would have to use an OCPD that is rated 240v at least and not 120/240 as with a 1ph3w system were there is commonly 120v L-N and L-G when you are supplying a 240v 1ph load.
 
kwired said:
My guess - no demand for them. Go to Europe where they have 415/240 volt systems and I'm sure they are common as 120 volt single pole breakers are here.
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:lol: You can get them by the yard. Even US makers are in the market:

http://apps.geindustrial.com/publib...NR=Application and Technical|GEZ-7927|generic

Interestingly, the AIC on them is lower in terms of the American versions. Willing to bet they are just 120 volt 22kaic breakers re listed for 240 volts at 9 or 3 kaic.
 
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