Do 230 or 240 motors work in my 277/480 v installation ?

[jor1492]

Hi all,
I have a question about if these motors can Work in my facility.
I have a 277/480 V 60hrz installation and I bought a 230 Volt motor and a 240 volt motor.
Do they Work in my 277/480 v installation ? Why ? what is the range of nominal voltaje machine that I can install in my 277/480v facility?
thanks in advance

 

[magoo2]

Usually a 460 V motor is used with a 480Y/277 V supply.

The motor nominal voltage rating is good within a +/- 10% voltage range. In other words, a 460 V motor can operate satisfactorily in the range of 414 to 506 volts. By satisfactory operation, I mean the motor will run and start properly within that range.

If you apply the same 10% tolerance to a 230 or 240 volt motor, the 277 V service is too high.

Keep in mind that the electric utility supply will have its own tolerance. A nominal 277/480 supply will have a tolerance of +/- 5%, so what you're calling 277 V can be as low as 263 V and as high as 291 V.

Refer to ANSI C84.1 for more details on this.

 

[waross]

First answer: NO, YOU CAN"T RUN A 230 or 240 Volt motor on 277 Volts or 480 Volts.
But;
Most 230 Volt 3 phase motors are dual voltage and will run on either 240 Volts or 480 Volts.
And;
230 Volts is the standard motor voltage in north America. Beware of the quality of motors rated at 240 Volts.
If these are single phase motors they will not be happy with 277 Volts.
You can probably use an auto transformer to drop the 277 Volts down to a usable voltage.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[jor1492]

Thanks guys , you were very helpfull.
I have a last query, Does the 240/480 V 3phase installtion exist? or is it the same that 277/480 V 3phase?

 

[waross]

The standard system voltages are 480/277 Volts and 208/120 Volts. Many 230 Volt motors will run on 208 Volts.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Mbrooke]

A 230 volt 50Hz motor will run fine at 277volts 60Hz, albeit the higher speed is taken into account.

 

[waross]

Is 230 Volts a standard IEC voltage? What are the standard IEC motor voltages?

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Mbrooke]

Yes, 230 volts is a standard IEC voltage. However, bear in mind that US motors are listed 230 volts meant for 240 volt supplies. So the OP may have either.

 

[peon7]

There are some 415Y/240 volt installations, mainly military and foreign.

 

[jraef]

Any consideration of tolerance of a 230V 3 phase motor is moot: you do NOT have 277V 3 phase available, you only have 277V from line to Neutral, so single phase only.

There are two voltage "Ckasses"; Distribution Class and Utilization Ckass. Distribution is what the utilities supply, Utilization is what the machinery (motor) manufactures build to. So for a 480V distribution system, motors are designed around 460V utilization, because you will expect a certain amount of voltage drop between the Service Entrance and the motor terminals. For a 240V distribution system, the utilization voltage is 230V and for a 208V distribution the utilization voltage is 200V.


"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

 

[genhead]

peon7

"[highlight #D3D7CF]There are some 415Y/240 volt installations, mainly military and foreign.[/highlight]"

Some of us might say there are some 480/277 volt installations, mainly military and foreign.