480Y 277 delta motor wiring

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Jraef said:
Most likely this is a Bonfiglioli (assuming so, because you said Italy) IEC motor that was originally DESIGNED to be used at 400V 50Hz when connected in Wye, then 230V 50Hz when connected in Delta. When connected in Wye, the V/Hz ratio of the motor is 8:1 (400/50). If you apply 480V 60Hz to is, the V/Hz ratio is still 8:1, so the motor will put out rated torque all day, every day, no problem. It will of course turn 20% faster.

But when Bonfiglioli gets the motor listed and labeled in North America, they sell it as a 480V rated motor. Then, BECAUSE people here might THINK it can also be connected to 230V, they explicitly make the nameplate say "277V" if connected in Delta, that way they will think twice about connecting it to 240V 60Hz, which would make it burn up.

So technically the motor is rated 480Y, 277V Delta, but not because anyone can USE it at 277V 3 phase since that doesn't exist. It just says that so that you know you CANNOT use it at anything but 480V when connected to a 60Hz system.
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Italian motors....arrgghhh! There should be a ban on importing them.
 
Jraef said:
Most likely this is a Bonfiglioli (assuming so, because you said Italy) IEC motor that was originally DESIGNED to be used at 400V 50Hz when connected in Wye, then 230V 50Hz when connected in Delta. When connected in Wye, the V/Hz ratio of the motor is 8:1 (400/50). If you apply 480V 60Hz to is, the V/Hz ratio is still 8:1, so the motor will put out rated torque all day, every day, no problem. It will of course turn 20% faster.
Click to expand...
Rated torque and 20% faster would result in 20% more power.
P=Tw

Could the motor dissipate the additional losses?
 
ggunn said:
I don't know from motors, but what does 277V delta mean? Three phase, three wires (no neutral) with 277V phase to phase?
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We are not talking about delta as applied to the power supply. We are talking about connecting the motor windings in a delta configuration. As Jeff said there is no standard wiring system that will supply 277 volts line to line, but that is what this motor would require if you the motor in a delta configuration.
 
don_resqcapt19 said:
... As Jeff said there is no standard wiring system that will supply 277 volts line to line, but that is what this motor would require if you the motor in a delta configuration.
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I have no idea where you guys are getting this cannot be wired 277 delta. It is a connection configuration and has nothing to do with the source having to be 277 delta. As I've been saying all along, it's simply the same connection as 480 wye, except you connect a 480/277V 3Ø 4W neutral to the joined leads (i.e. optional; also unnecessary in the vast number of cases). It amounts to wiring each motor winding with 277V either way with wye having a floating neutral point, delta not.
 
If the source is wye, you will have a problem connecting the motor windings to the three hots and getting 277 line to line. As long as both ends of each winding are brought out independently you could connect each coil line to neutral, but that would not be a delta config of the windings as probably required by the installation instructions. :)
 
When each lead is brought out independently (and for reference, we are talking about a six-lead 3Ø motor), all that matters to the motor is the voltage, hertz, and phase relationships of each winding supply.
 
Smart $ said:
When each lead is brought out independently (and for reference, we are talking about a six-lead 3Ø motor), all that matters to the motor is the voltage, hertz, and phase relationships of each winding supply.
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And when you connect the windings in delta, you end up with 3 points to connect the power supply wires. What standard power system will give you 277 volts line to line?
 
Smart $ said:
I have no idea where you guys are getting this cannot be wired 277 delta. It is a connection configuration and has nothing to do with the source having to be 277 delta. As I've been saying all along, it's simply the same connection as 480 wye, except you connect a 480/277V 3Ø 4W neutral to the joined leads.....
Click to expand...
Trying to make sure I understand....You are saying L1 to T1, L2 to T2, L3 to T3, Neutral to 4,5,6. Is that correct?

That would give you 277V to the windings but they will still be configured for a 480V connection so the motor is not going to be happy.
 
don_resqcapt19 said:
And when you connect the windings in delta, you end up with 3 points to connect the power supply wires. What standard power system will give you 277 volts line to line?
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With independent leads, I'm just trying to point out what is depicted in the following diagram:

windings.gif
 
I'll try and get a pic of the nameplate Monday. There are 3 motors on this machine. The other 2 are listed at 50hz. The oddball sounds like it might be what Jraef described,
a Bonfiglioli or something similar.

Someone asked about control voltage, it is 24VAC and it has a transformer than can accommodate other voltages. This machine is nothing fancy the controls are minimal and
packed into an undersized plastic box. And it has been around awhile, definitely not a new piece by a long shot.
 
Jraef said:
Most likely this is a Bonfiglioli (assuming so, because you said Italy) IEC motor that was originally DESIGNED to be used at 400V 50Hz when connected in Wye, then 230V 50Hz when connected in Delta. When connected in Wye, the V/Hz ratio of the motor is 8:1 (400/50). If you apply 480V 60Hz to is, the V/Hz ratio is still 8:1, so the motor will put out rated torque all day, every day, no problem. It will of course turn 20% faster.

But when Bonfiglioli gets the motor listed and labeled in North America, they sell it as a 480V rated motor. Then, BECAUSE people here might THINK it can also be connected to 230V, they explicitly make the nameplate say "277V" if connected in Delta, that way they will think twice about connecting it to 240V 60Hz, which would make it burn up.

So technically the motor is rated 480Y, 277V Delta, but not because anyone can USE it at 277V 3 phase since that doesn't exist. It just says that so that you know you CANNOT use it at anything but 480V when connected to a 60Hz system.
Click to expand...

Have they been making these for awhile? I don't know the age of this thing but it isn't new and the controls are so minimal as to not match what I have seen on newer Italian equipment. Dang Jraef, how
did you learn all this stuff? You have seen a lot for sure. I have seen a fair amount myself but I can't seem to retain it nearly as well as you do!:dunce:
 
Smart $ said:
When each lead is brought out independently (and for reference, we are talking about a six-lead 3Ø motor), all that matters to the motor is the voltage, hertz, and phase relationships of each winding supply.
Click to expand...
To just run, sure. You can always run an unloaded motor on lower voltage, but to run right and do the work it's supposed to do voltage has to be right for the way the windings are configured.
 
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