440v motor on 480v supply

Status
Not open for further replies.

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
If your 480V supply has a 5% tolerance it could be 504V.
Thus 14.5% above the 440V rating of the motor.
What's your answer to a 110v motor on 120v, or a 220v motor on 240v, such as described in post #18?

I remember the forum having the collective opinion that the voltage "mismatch" is intentional and beneficial.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
drcampbell, post 3, pretty well nailed it. What is to lose? The motor won't sell for anything useful.

Connect it, run it under load, check the current. The magnetizing current will be a bit high. But if the motor is not heavily loaded, it will be fine.

If the current is over the nameplate, then consider doing something. It is a 1.0 SF motor, so set the overloads to 115%. If the overloads trip, Start looking for a new motor or a transformer

Price out the new motor and compare with a transformer. I've never seen a 480D/440Y transformer. SQD and Acme don't show any - probably a special order, which is never a good idea.
If you do decide on a transformer, consider getting a 480D/480Y with 2 - 2 1/2% taps up and down. Set 5% high, and connected to 480V will give 456V on the Wye secondary.

The motor starting current will sag the secondary voltage from the transformer impedance. Recommend getting a transformer rated at least 1.5 times the motor FLC - 45KVA, 30 kva is small.

Depending of the cost of the machinery, the price of a new motor (or the transformer) may send the customer into conniption fits.

good luck. Let us know how it comes out
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
drcampbell, post 3, pretty well nailed it. What is to lose? The motor won't sell for anything useful.

Connect it, run it under load, check the current. The magnetizing current will be a bit high. But if the motor is not heavily loaded, it will be fine.

If the current is over the nameplate, then consider doing something. It is a 1.0 SF motor, so set the overloads to 115%. If the overloads trip, Start looking for a new motor or a transformer

Price out the new motor and compare with a transformer. I've never seen a 480D/440Y transformer. SQD and Acme don't show any - probably a special order, which is never a good idea.
If you do decide on a transformer, consider getting a 480D/480Y with 2 - 2 1/2% taps up and down. Set 5% high, and connected to 480V will give 456V on the Wye secondary.

The motor starting current will sag the secondary voltage from the transformer impedance. Recommend getting a transformer rated at least 1.5 times the motor FLC - 45KVA, 30 kva is small.

Depending of the cost of the machinery, the price of a new motor (or the transformer) may send the customer into conniption fits.

good luck. Let us know how it comes out
Why not an auto transformer at a fraction of the size?
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
Great idea. Got a spec for a COTS, available in the US?
Preferably one that uses US customary units (kBTU/hour) and not metric electricity (kVA)

I didn't see anything - not even a 3-pot BB that looked suitable

But, first - hook it up and run it under load - and if it doesn't overheat ......
.

.

.

.

Move on
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
Great idea. Got a spec for a COTS, available in the US?
Preferably one that uses US customary units (kBTU/hour) and not metric electricity (kVA)

Move on
kVA isn't metric.
How many metres in a vol or an amp??
It's SI.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
I'll take that to mean you didn't see one either.
(Deleted comment about SI measuring fuel consumption in mm^2)
 

drcampbell

Senior Member
Location
The Motor City, Michigan USA
Occupation
Registered Professional Engineer
kVA isn't metric.
How many metres in a volt or an amp??
It's SI.
A volt is a meter2 · kilogram · second-3 · Ampere-1.
https://www.nist.gov/pml/special-pu...hapter-4-two-classes-si-units-and-si-prefixes

"The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross section, and placed 1 meter apart in vacuum, would produce between these conductors a force equal to 2 × 10−7 newton per meter of length."
https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-definitions-si-base-units

And a Volt·Amp is a meter2 · kilogram · second-3.
 

MAC702

Senior Member
Location
Clark County, NV
Some things are worth being pedantic about. That ain't.

Thou shalt not use the commonly understood term "metric!" Thou shall use a French initialism instead! LOL.

Chalk it up to colloquialism, if you like. "Metric" is perfectly understood by EVERYONE. And many will know what you mean when you say "SI." Feel free. Stop "correcting" people about it.

God forbid we use any jargon, even if that is what you want to insist that's all it is.
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
Chalk it up to colloquialism, if you like. "Metric" is perfectly understood by EVERYONE.
Clearly it isn't. No problem. Now. shall we get back on topic?
Operating a motor outside manufacturer's stated limits is just daft.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
Uhhh ... My post 25 comment, "Preferably one that uses US customary units (kBTU/hour) and not metric electricity (kVA)", was supposed to be mild engineering humor poking fun about units.

Regardless, dr, MAC you are both right on target.
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
Uhhh ... My post 25 comment, "Preferably one that uses US customary units (kBTU/hour) and not metric electricity (kVA)", was supposed to be mild engineering humor poking fun about units.

Regardless, dr, MAC you are both right on target.

Yes, OK.
I'm an old bloke. I know the units, Imperial, CGS, MKS, and can do most of the conversions mentally. I know what an acre of land is is square yards, pints (of beer) and litres of milk.
It doesn't make any of them wrong. But SI is so much simpler.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
TECO motors made for use in North America are made at the old Westinghouse motor plant in Round Rock, Texas. Yes, the NEMA design specs for motors in North America is +-10% of the nominal nameplate voltage.

But that is not what this motor is, this one was made in Taiwan and given the Chinese writing on the plate, the IEC efficiency references and non-compliant voltages listed, it’s not a NEMA design motor, it’s an IEC designed motor with a new set of data points on the nameplate for using on 60Hz. Most likely with our typical line voltage swings, this motor will saturate, run hot and have a foreshortened lifespan, as well as possible giving you additional torque stresses on starting (unless you have a soft starter or VFD). That foreshortened lifespan might still be 5 years from now, it might be 5 months, there is no way of predicting.

But here’s the thing; they ALREADY OWN IT and it’s already mounted into the machine. In addition, finding, mounting, wiring and protecting a buck-boost transformer to buck the 480 down to 440 for this small of a machine is not likely worth the effort; there is no reasonable payback. So were it me, I would just hook it up, get whatever life they can out of it, and to minimize down time when it does fail, get all of the mounting and shaft details off of it to order a spare now so that it is waiting in the wings ready to swap out. Then take this one to a rewind shop and have it rewound as a 460V motor to keeps as the new spare (although at 25HP, it may not be worth it compared to just buying a new one).

Side note; IEC motors like this will require Class 10 overload protection and they have NO service factor, so pay attention to that in selecting the OL settings.
 
Last edited:

RumRunner

Senior Member
Location
SCV Ca, USA
Occupation
Retired EE
Some things are worth being pedantic about. That ain't.

Thou shalt not use the commonly understood term "metric!" Thou shall use a French initialism instead! LOL.

Chalk it up to colloquialism, if you like. "Metric" is perfectly understood by EVERYONE. And many will know what you mean when you say "SI." Feel free. Stop "correcting" people about it.

God forbid we use any jargon, even if that is what you want to insist that's all it is.

Using SI is appropriate term and it is not colloquialism.

Metric is not often used in academia like it used to.

Although some consider colloquialism as a style. . . it is considered vulgar or incorrect. . . which SI is not.

Metric has been abrogated. . . it is an old school legacy.

The base unit of meter that defines unit of length is the coherent unit of volume.

In the context of wood (for firewood)-- metric-- the volume is referred to as: a cord of wood.

You may still keep it alive (metric) if you live in the boondocks where you purchase and use wood for cooking and heating.

SI is now the mainstream. . . in science and it is not colloquial.

And I agree with Bes, it is a YES for SI


It also means YES in Spanish.
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
TECO motors made for use in North America are made at the old Westinghouse motor plant in Round Rock, Texas. Yes, the NEMA design specs for motors in North America is +-10% of the nominal nameplate voltage.

But that is not what this motor is, this one was made in Taiwan and given the Chinese writing on the plate, the IEC efficiency references and non-compliant voltages listed, it’s not a NEMA design motor, it’s an IEC designed motor with a new set of data points on the nameplate for using on 60Hz. Most likely with our typical line voltage swings, this motor will saturate, run hot and have a foreshortened lifespan, as well as possible giving you additional torque stresses on starting (unless you have a soft starter or VFD). That foreshortened lifespan might still be 5 years from now, it might be 5 months, there is no way of predicting.

But here’s the thing; they ALREADY OWN IT and it’s already mounted into the machine. In addition, finding, mounting, wiring and protecting a buck-boost transformer to buck the 480 down to 440 for this small of a machine is not likely worth the effort; there is no reasonable payback. So were it me, I would just hook it up, get whatever life they can out of it, and to minimize down time when it does fail, get all of the mounting and shaft details off of it to order a spare now so that it is waiting in the wings ready to swap out. Then take this one to a rewind shop and have it rewound as a 460V motor to keeps as the new spare (although at 25HP, it may not be worth it compared to just buying a new one).

Side note; IEC motors like this will require Class 10 overload protection and they have NO service factor, so pay attention to that in selecting the OL settings.

Interesting. But IEC? The IEC would suggest for the European market but Europe is 50Hz and 400V.
I don't know any country that is 440V, 60Hz.

UK used to be 440V/250V but never 60Hz.

A puzzler
 

Besoeker3

Senior Member
Location
UK
Occupation
Retired Electrical Engineer
Using SI is appropriate term and it is not colloquialism.

Metric is not often used in academia like it used to.

Although some consider colloquialism as a style. . . it is considered vulgar or incorrect. . . which SI is not.

Metric has been abrogated. . . it is an old school legacy.

The base unit of meter that defines unit of length is the coherent unit of volume.

In the context of wood (for firewood)-- metric-- the volume is referred to as: a cord of wood.

You may still keep it alive (metric) if you live in the boondocks where you purchase and use wood for cooking and heating.

SI is now the mainstream. . . in science and it is not colloquial.

And I agree with Bes, it is a YES for SI


It also means YES in Spanish.

Thank you kindly, sir. People here (UK) still refer to their height in feet and inches and their weight in stones and pounds. If I tell someone that I weigh 75kg or that my jolly big dog is 40kg I get blank looks most of the time.

Go for a medical examination and it is all metres and kilograms.

The HUGE beast with the shiny coat...

AaI4b4r.jpg
 
Last edited:

Russs57

Senior Member
Location
Miami, Florida, USA
Occupation
Maintenance Engineer
No idea how hard it would be to find a 180MC frame motor in the states.

I know the Danfoss motors are dual rated 380-420 @ 50 hertz and 440-480 @ 60 hertz. But then I'd expect the KW to be 18.5 and 22.2. I'm no expert on motors but I think that would require a 12 lead motor.

I reckon I'd make a decision based on how difficult it would be to source a new motor vs cost of downtime.
 

iceworm

Curmudgeon still using printed IEEE Color Books
Location
North of the 65 parallel
Occupation
EE (Field - as little design as possible)
...

Although some consider colloquialism as a style. . . it is considered vulgar or incorrect. . . which SI is not.

...

The base unit of meter that defines unit of length is the coherent unit of volume.

...
(SLAP)
Well I have been put in my place. I don't recall the last time I was accused of being "vulgar" - "uncouth" regularly, but not vulgar.

I promise I will henceforth no longer use kBTUs/hour (apparent) to rate transformers. Moving forward, I will use kJoules/second (apparent)

And in the interest of harmony, I will no longer use gallons/mile for fuel consumption. I will now use mm^2 per 100,000.

The base unit of meter that defines unit of length is the coherent unit of volume.
Without accusing you of any in-appropriate, colloquialism, shouldn't that have been "metre"?



the worm
(turneth - and begins to dig
 
Status
Not open for further replies.
Top