All motor are design suitable to operate with different starters?

[Michael2009]

Hi Guys,

all motor design suitable operate by different starter? I mean, we do not need to consider starter type example like DOL, Soft Starter and VFD when we purchase a motor?
We can decide on starter type later..

BR
Michael

 

[LionelHutz]

Well, some motors are more suitable for use with a specific type due to their characteristics, but generally speaking soft-starters or VFDs can be used on most motors. A filter may be required on the output of the VFD to ensure the voltage waveform is safe for the motor.

There are winding standards for a motor used on a VFD, but most manufacturers these days build their motor the same way regardless of it being the standard or "VFD rated" model. The wire insulation is so good these days that it's almost all capable of meeting the VFD specification.

There are some starter types that require specific motors such as 6 or 12 lead motors are required for wye-delta starters and 2 winding motors are required for part winding starters.

 

[jraef]

Although the winding insulation issue is generally true, there are other issues such as cooling, balancing and bearing insulation or grounding that factor into motors designed to be run from VFDs. It is much more application specific than motor specific, because sometimes you need those added features, sometimes not. Without considering the application, you can either set yourself up for failure by ignoring something you should not have ignored, or waste budget money buy paying extra for something you didn't need.

As to electro-mechanical starters, not all motors can be started via Wye/Delta (Star/Delta), or Part Winding (PW) starting, the windings need to be configurable to accomplish those methods.


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

 

[threshold77]

I also have a question that is somehow related to the original question. I have 4 identical motors. 2 of them I used with vfd and the other 2 with soft-starters. The motors that I used with vfd, can I used them with soft-starters? and vice-versa? I believe that there would be no problem about this but my colleagues are contesting about it.

Thank you in advance for your feedback.

 

[jraef]

There is nothing special about starting a motor with a soft starter. So you do not need s special inverter rated motor, but if you have one, it can certainly be started with a soft starter.


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

 

[waross]

One exception may be the wound rotor motor. Wound rotor motors start best with full resistance in the rotor circuit which is shorted out in steps as the motor accelerates. If a wound rotor motor has the rotor slip rings shorted so as to be started with a VFD or a soft starter, the starting torque will be low and may not be able to accelerate the load.

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

 

[LionelHutz]

A wound rotor induction motor with a small single step of rotor resistance works well with a soft-starter. The same motor with shorted slip rings will also work on a properly chosen VFD.

 

[Michael2009]

Hi guys...
thanks for reply.

I have one supplier ABB.. propose
motor series
M3KP and M3JP. Is a DOL motor. They confirm this motor can operate by DOL or soft starter but not VFD.

Other vendor. I am not sure.

BR
Michael

 

[jraef]

That's generally true of "purpose built" motors; it just means the motor is designed for a specific use rather than general purpose, so they do not waste money on features they know will not be necessary. Most motor manufacturers do that, especially for OEMs (Original Equipment Manufacturers) who do not want to spend any more than is absolutely necessary.


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

 

[LionelHutz]

Those motors are explosion proof, right? IF so, the motor would likely work fine with a VFD but lose it explosion proof rating. There are special rules for that type of motor that has to be followed.

 

[ScottyUK]

Many of ABB's flameproof motors are qualifed for VFD use with specific VFDs (ABB ones, naturally ;-) ) and at a certain temperature class, T4 I think. You have to specify VFD duty when ordering, and the maker's plate will list the limits such as maximum and minimum speed. As Lionel says, a standard Ex'd' motor can't be used on a VFD.