440 volt machine on 480 volt system ?

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Davebones

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North Of Tampa Fl
I've been informed we have a new hydraulic press coming . The only information I have received is it will need ( 440 Volt , 35 amp , 3 phase circuit ) . I assume this might be coming from Germany . The paper I saw said ( 440 volt + - 5 % ) = 462 volt's . Trying to get the manufacture to verify if 480 volt will be ok . Wondered if this has been a issue for anyone else ?
 
IMO it should work but obviously you need to check with the manufacturer. The NEC lists a range of 440-480 in Article 430.

Table 430.250 Full-Load Current, Three-Phase Alternating-Current Motors
The following values of full-load currents are typical for motors running at speeds usual for belted motors and motors with
normal torque characteristics.
The voltages listed are rated motor voltages. The currents listed shall be permitted for system voltage ranges of 110 to
120, 220 to 240, 440 to 480, and 550 to 1000 volts.
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Davebones said:
I've been informed we have a new hydraulic press coming . The only information I have received is it will need ( 440 Volt , 35 amp , 3 phase circuit ) . I assume this might be coming from Germany . The paper I saw said ( 440 volt + - 5 % ) = 462 volt's . Trying to get the manufacture to verify if 480 volt will be ok . Wondered if this has been a issue for anyone else ?
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Yes, try to get written confirmation from your supplier, who may or may not be the manufacturer, that it will work on 480V, 60Hz.
The supply in Germany is the "harmonised! European 400V, 50Hz.
The Press may be coming from Germany but the individual components could be from anywhere.
 
Make sure it is not rated 50 Hz. Something tells me it is.

Motors will run faster if applied to 60 Hz and connected across the line.
 
kwired said:
Make sure it is not rated 50 Hz. Something tells me it is.

Motors will run faster if applied to 60 Hz and connected across the line.
Click to expand...
And take more power - cube law with speed if the pump is centrifugal.
As I said, the OP needs to get his supplier to confirm that the motor is adequately rated for the 480V, 60Hz duty
 
Is this a large motor, i.e. over 250HP?

Weg, the Brazilian motor mfr., does an odd (yet explainable) thing with some of their large motors, especially their "crusher duty" versions.
1) They are DESIGNED for 660V 50Hz, Star (Wye) connected, because that is what they use in mining applications in Brazil.
2) That design then means they have a V/Hz ratio of 660/50 = 13.2V/Hz
3) When used at 60Hz, the equivalent motor voltage in Star (Wye) would be 13.2 x 60 = 792V, but nobody uses 792V
4) But if you reconnect the motor internally in a Delta pattern, the effective voltage becomes 762 / 1.732 = 440V 60Hz

I have used dozens of those Weg motors on rock crusher applications over the years. Although I not a fan of the physical construction of their motors (the shafts can sag), electrically they are absolutely fine with being run on 480V systems. 440 + 10% = 484V. But if your utility line tends to run high at night, you might want to look at tapping it down. Yours may not be Weg, but may be following the same concept: designed as 660V 50Hz when connected in Star, usable as 440V 60Hz by connecting it in Delta.
 
Jraef said:
Is this a large motor, i.e. over 250HP?

Weg, the Brazilian motor mfr., does an odd (yet explainable) thing with some of their large motors, especially their "crusher duty" versions.
1) They are DESIGNED for 660V 50Hz, Star (Wye) connected, because that is what they use in mining applications in Brazil.
2) That design then means they have a V/Hz ratio of 660/50 = 13.2V/Hz
3) When used at 60Hz, the equivalent motor voltage in Star (Wye) would be 13.2 x 60 = 792V, but nobody uses 792V
4) But if you reconnect the motor internally in a Delta pattern, the effective voltage becomes 762 / 1.732 = 440V 60Hz

I have used dozens of those Weg motors on rock crusher applications over the years. Although I not a fan of the physical construction of their motors (the shafts can sag), electrically they are absolutely fine with being run on 480V systems. 440 + 10% = 484V. But if your utility line tends to run high at night, you might want to look at tapping it down. Yours may not be Weg, but may be following the same concept: designed as 660V 50Hz when connected in Star, usable as 440V 60Hz by connecting it in Delta.
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Assuming the application is OK with the higher RPM.
 
Besoeker said:
Assuming the application is OK with the higher RPM.
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:thumbsup:
With a rock crusher you can control the infeed to limit the power required of the motor, as long as the machine parts are OK with the higher impact speed.
With a pump or fan, the higher RPM would only be OK if there were flow limiting or an impeller redesignto keep the mechanical power demand within the motor's limits.
 
GoldDigger said:
:thumbsup:
With a rock crusher you can control the infeed to limit the power required of the motor, as long as the machine parts are OK with the higher impact speed.
With a pump or fan, the higher RPM would only be OK if there were flow limiting or an impeller redesignto keep the mechanical power demand within the motor's limits.
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Or just get the right pump in the first place.........:)
That's why I think important that the OP gets written confirmation from his supplier that the motor is suitable for the supply it intended to be used on. Before the order is placed if it isn't too late already.
 
Besoeker said:
Or just get the right pump in the first place.........:)
That's why I think important that the OP gets written confirmation from his supplier that the motor is suitable for the supply it intended to be used on. Before the order is placed if it isn't too late already.
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In a perfect world, yes, absolutely.

In reality, most ELECTRICIANS only get brought into the process at the very END when it's time to make the connections, after all of the decisions have been made by other less involved parties; often "bean counters" or weaker minds under the influence of bean counters.

"Ooh, ooh, buy that one from Germany, it's used but it's cheaper."
"But we don't know if it will work here, the specs seem a little off."
"Meh, don't worry about that, the electricians will take care of it when it gets here."
 
Jraef said:
In a perfect world, yes, absolutely.

In reality, most ELECTRICIANS only get brought into the process at the very END when it's time to make the connections, after all of the decisions have been made by other less involved parties; often "bean counters" or weaker minds under the influence of bean counters.

"Ooh, ooh, buy that one from Germany, it's used but it's cheaper."
"But we don't know if it will work here, the specs seem a little off."
"Meh, don't worry about that, the electricians will take care of it when it gets here."
Click to expand...
In which case I think the OP should take it up with whoever placed the order.
We don't know who the motor manufacturer is, what it's intended application is except possibly not mining at that rating, we don't know if it will be OK at 480V, 60Hz. And we don't if the driven machine could take a 20% increase speed or even that were to happen.

I think the OP is correct to query the rating. It would be better to clarify that as soon as possible. A new motor and pump if that's what it needs would be would be a lot less hassle than skimming the impeller and be more efficient in operation. Same goes for a flow restriction.

In short, there are more questions than answers.
 
Fulthrotl said:
you are screwing with our rampant speculation here.

over here, on this side of the pond, we've had a year of training
in the wildest types of speculation. references upon request.

hold our beers, we've got this.
Click to expand...
If it were not for jumping to conclusions and running with hunches, I would get no exercise at all...
 
Fulthrotl said:
you are screwing with our rampant speculation here.

over here, on this side of the pond, we've had a year of training
in the wildest types of speculation. references upon request.
Click to expand...
I think those are international sports............:D
 
Besoeker said:
And take more power - cube law with speed if the pump is centrifugal.
Click to expand...

Hydraulic press ... 99.99999% certain positive displacement, linear with speed ... although if fixed, vs variable, fluid friction losses would increase.
 
Jraef said:
Also,


Assuming this is the HPU motor, it would most likely be positive displacement, not centrifugal. Probably a gear pump.
Click to expand...

Gear pumps are, IME, far less common than vane or piston at the (guessed from 35A) 25HP/20kW size. Else, I agree.
 
Davebones said:
I've been informed we have a new hydraulic press coming . The only information I have received is it will need ( 440 Volt , 35 amp , 3 phase circuit ) . I assume this might be coming from Germany . The paper I saw said ( 440 volt + - 5 % ) = 462 volt's . Trying to get the manufacture to verify if 480 volt will be ok . Wondered if this has been a issue for anyone else ?
Click to expand...


The paper I saw said ( 440 volt + - 5 %
Click to expand...

I agree, get the specs info from the manufacture or supplier, to furnish the manufacture's specs. Especially if the equipment is under warranty. Get the specs in writing. The specs should also show the AC mains frequency.

You might want look at installing buck transformers to lower the voltage to 440Vac.
 
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