Hi there, Can anyone help to shed

[necr]

Hi there,
Can anyone help to shed some light about the so called three phase induction motor energy saver which allegedly can save the energy consumption of the motor by as much as 25%. My employer requested the feasibility study. Pity the claimant doesn’t want to disclose the principle of operation and also they don’t want to disclose the variables which I should measure to notice the effects, they just say it works.. Please help

Regards,

 

[Baldor]

I looked (skeptically) into one so called "green" energy saver for single phase motors. It was basically a resistor that reduced the voltage at the motor. This will improve the motor power factor, but reduce torque and increase slip.

There's another active type saver the supposedly monitors the power factor and reduces/increases voltage when needed.
The best thing to do is to size your motor for the application; make sure your running at at least 3/4 load.

 

[cuky2000]

Electric motor efficiency is only one of multiple areas to be considered in a bigger picture to improve the overall energy efficiency in a facility. The efficient of the mechanical equipment that the driver move such as pump, fan, machine, etc should be considered in the analysis.

In some instance, the efficient of a motor could be increased if the motor is rebuild.

SUGGESTION: Check with DOE and other organizations for guide, publications and software available.

http://www.oit.doe.gov/bestpractices/motors/factsheets/chevron.pdf

http://www.oit.doe.gov/bestpractices/motors/factsheets/mc-2463.pdf

http://www.ul.com/media/newsrel/nr022103.html

 

[busbar]

Search on “motor energy saver” at this site. Similar devices have been discussed here.

 

[rbulsara]

If the vendor is not willing to demonstrate how his/her product works, I would be very skeptical to buy it.

Verification is very simple, have him/her hook up one of his/her 'demo' or test product (at no charge of course) to one of your motors and setup kW and amp meters. Take readings with and without the 'energy saver'. If you do not see any significant reduction in kW, (and only kW) do not fall for the product!

Reduction is kvA or pf is irrelavant, you do not need a 'energey saver' for that as there are other proven avenues for them.

baldor's suggestion is a good one to size the motor correctly.

Plus motor draws what it needs, so I am personally skeptical of such energy saver gismos.

 

[dmel]

They use better quality stampings in the core and purer copper in the winding. I have seen in some cataolgs that the savings is between 5 - 10%. How 25% is achieved is not clear. However, it is essential that whichever motor you select, it should run at close to full load. THerefore, motor sizing is important. This would help conserve energy in a better manner.