2 hp motor 4

[insideman]

Where can I get a two horsepower 3 phase 60hz 1200 rpm motor with a face mount?

 

[itsmoked]

http://www.grainger.com/Grainger/wwg/itemDetailsRender.shtml?xi=xi&ItemId=1613544866&ccitem=

And A VFD?

 

[insideman]

Thanks for the tip. However, the rpm is not right.

 

[stardelta]

You will find something very close here.

http://www.baldor.com/products/ac_motors.asp

 

[stardelta]

Here`s one.

http://www.baldor.com/products/deta...Purpose&winding=36WG0197&rating=40C+AMB-CONT#

 

[Barry1961]

You may be able to use a more common 1800 rpm motor and control the speed with a VFD.

Barry1961

 

[insideman]

Thanks all!

The Baldor unit is close, but very pricey.

Iknow this is a bastard rpm, but it is what the client wants.

 

[stardelta]

I dont think there is anything at all unusual about the motor. Its a standard speed for a 6 pole machine @60hz and Baldor wont be the only company to offer them. Just by doing a bit of idle surfing I found this one. Try contacting a few local motor suppliers or repair companies and see what they can offer you.

http://www.electricmotorwarehouse.com/three_phase_cface_nobase_TEFC.htm

(Item #131525)

 

[waross]

You will not find an induction motor running at 1200 RPM.
You will find an induction motor running at 1200 RPM minus the Slip RPM. The actual speed will be less than 1200 RPM but probably more than 1100 RPM.
We reffer to six pole motors as 1200 RPM because that is the speed that they approach but never reach.
Equipment manufacturers make allowance for this small speed difference when rating their equipment. An application requiring EXACTLY 1200 RPM at 2 HP. is very unusual and probably the result of a misunderstanding.
You need a synchronous motor or a VFD. If the speed is that critical, you may have to add speed feed back to the VFD.
What do you intend to drive?
yours

 

[stardelta]

Incidently, and I have overlooked this fact, if you do require exactly 1200rpm you will need to use a VFD as previously mentioned. 1200 rpm is the Synchronous speed of the motor, the theoretical maximum that assumes no load or losses and does not account for slip. The 1140 rpm figure is the speed the motor actually rotates at under ideal full load conditions and is termed the Asynchronous speed. You need clarification from your customer over the exact speed required. A suitable VFD for this application could well cost as much if not more than the motor itself.

 

[waross]

If the 1140 RPM is acceptable, and the problem is the cost, be aware that a 1200 RPM motor is 50% larger than a 1800 RPM motor. If you check the frame size charts you will see that the same frame will be used for a 5HP 1200 RPM motor as a 7.5 HP 1800 RPM motor. Expect to pay at least 50% more, plus added costs because it is not sold in the volumes that 1800 RPM motors are. Twice the price of an 1800 RPM motor at the same HP. would not be unreasonable.
yours

 

[itsmoked]

And hence we are back to why I first suggested a 1725 and and a Variable Frequency Drive....

It might even be cheaper to get a 1725 AND a VFD.

waross's description also fits the 1800 -> 1725 and 3600 -> 3450.

 

[aolalde]

When VFDs are applied, the output HP that a motor delivers at reduced frequency will be reduced too. That will traduce in larger motor size when the base speed of the selected motor is far apart from the operational speed, since the performance of the motor is based on constant torque.
1750/1200* 2 = 2.91 (need a 3 HP motor for 1750 rpm or 4 poles)
3560/1200*2 = 5.93 (at least needs 5 HP for 2 pole motor)

The last two options could result in more expensive solutions.

 

[jraef]

It depends on the nature of the load. If he needs the TORQUE of a 2HP motor at 1200 RPM, then OK. If he needs all 2HP at 1200RPM and he buys a 2HP 1800RPM motor/drive, it will only deliver 1.3HP at that speed. He would need to buy a 3HP motor/drive.

Eng-Tips: Help for your job, not for your homework Read faq731-376

 

[insideman]

Lots of good info! Thanks! To clarify, slightly less than 120 rpm is ok, so theLeeson motor may be usable. Pricy!

 

[stardelta]

Insideman??
We can give help and advice but cant do anything about costs