Premium Efficient VHS Motors 2

[BGD011]

Is there any National Standard for Vertical Hollow Shaft PREMIUM EFFICIENT Motors such as EPAct for horizontal?
How to define "Premium Efficient" motors?
The nominal full load eff on Premium Eff Motors has to be over 93.6%!?

Thank you in advance!

 

[BGD011]

Could anyone, please let me know something else about a "standard" in USA for PREMIUM EFFICIENCE VHS motors?

Thanks!

 

[rbulsara]

try vising websites of leading motor manufactures in the USA.

Reliance is one I have heard of. Baldor is other (not sure that fall under "leading").

I think word premium effieciecy is term used by manufactures, and not directly related to any standard. Check NEMA MG standards and some Energy Codes which in fact specifies efficiencies for motors and transformers. Energy Codes vary by states here. But ASHRAE may have some published documents on this.

I do not deal with this type of work in such detail, so only can give you some hints. Hope fully someone expert in motor specs can help you.

 

[dpc]

The efficiency is going to depend a lot on the motor size and especially speed. If this is a low rpm application, efficiency will be lower.

I don't believe the NEMA efficiency standards extend to vertical hollow-shaft motors, but I'm not sure about that. Best approach is to get the manufacturers to give you an expected efficiency then put something in your motor spec to require a minimum efficiency that at least of couple of suppliers can meet.

Remember the difference between nominal or average efficiency used in NEMA specs and minimum guaranteed efficiency.

 

[BGD011]

Thank you: rbulsara & dpc!

I am trying to get something from GE and US Motors,...

The motors to be nominal 3600RPM, 25Hp/3ph/60Hz/460V and each VFD/ATL started.

Dpc could you, please tell me more about:

"Remember the difference between nominal or average efficiency used in NEMA specs and minimum guaranteed efficiency."

Thanks a lot!

 

[rbulsara]

Refer to this link, it may be useful to you or you may already know about it. There are links within this link too.
Google search is a very useful tool.

http://www.cee1.org/ind/motrs/motrs-main.php3

 

[dpc]

The efficiencies given in NEMA standards refer to an average efficiency for all motors of a particular category. Then NEMA defines an allowable deviation from this average value. So a motor with a specified NEMA nominal efficiency can actually have an eff. that is lower than what on the nameplate and still meet NEMA standards.

A "minimum guaranteed efficiency" is just that. The manuf. will warrant that for this particular motor, it will have an eff. of at least this amount. In actuality, it will probably be higher than this.

If you are specifying a required efficiency, you must be clear if this a nominal value per NEMA or a minimum guaranteed value. You should also specify a test method to be used as the basis for the efficiency. The motor standards differ on how efficiency is measured and calculated.

It's generally worthwhile to specifiy a high-efficiency motor, but just specifying "high-efficiency" doesn't really buy you anything - you have to be more specific.

 

[Farkel]

Premium could be any value over that of EPACT.