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Performance Controller 1

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reebelec

Industrial
Sep 28, 2001
18
We have been looking at the performance controllers from the Power Efficiency Corp. The controller is a soft start with an scr motor controller of sorts. My background is controls not motors so I'm not sure how to word my question.
I'm wondering can any damage be done to the motor by running such a controller on it. Does anyone out there use or looking at using these. Are their claims of power savings
close to what the actual is?
Thanks for any input.
 
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Try searching this forum. This has been discussed many times before. If your motor is normally running at extremely low loads, there is some slight possibility of energy savings. In most cases, the actual energy savings are insignificant to non-existent.

Another way to look at it - if these devices could save as much energy as claimed - why isn't everyone using them?

 
Suggestions to reebelec (Industrial) Mar 26, 2004 marked ///\\We have been looking at the performance controllers from the Power Efficiency Corp.
///Please, post a website that you are dealing with, if it exists.\\ The controller is a soft start with an scr motor controller of sorts. My background is controls not motors so I'm not sure how to word my question.
I'm wondering can any damage be done to the motor by running such a controller on it.
///It depends on the motor soft starter (as you call it controller) output. Check with the motor manufacturer tech support for recommendations.\\ Does anyone out there use or looking at using these. Are their claims of power savings close to what the actual is?
///Ask for a demonstration pertaining to your application.\\
 
reebelec,
Do a Keyword Search in this forum using the term "Energy Saver" and you will get many many threads that will sum up to what dpc said so eloquently above. Performance Controls is just another one of the new breed of these people trying to sell an establish technology (solid state soft starters) on a misguided perception of "energy savings" because as a soft starter, theirs is less than spectacular and typically more expensive than the host of other soft starters available from well established reputable companies. This is probably because they have to support a mulitude of investors that were duped into forking over money for a "miracle" new technology that has been around for years.

Oops, my bias is showing again...

Regarding your question about motor damage, the short answer is NO. In fact any soft starter will provide you with the benefits of lower wear and tear on the motor itself, so one could agrue that it will extend the useable life. In the "energy saver" mode the SCRs are phase-angle fired all of the time, creating increased harmonics in the system and the motor circuit so there is a disproportionate increase in motor heating per output amp. That said, of course it is only in "energy saver" mode when the load is virtually gone, so the output amps are lower to begin with and net effect of said heating on the motor is null. If however the harmonics become a problem for you and you need to add a reactor in front of the Performance Contoller to mitigate them, then the voltage drop through the reactor will translate to a loss of torque in the motor when it is running at full speed, so it will run hotter than normal and theoretically fail sooner. The irony of course is that if you add the reactor to mitigate the harmonics created by the energy saver, the energy saved is now wasted in the reactor!

"Venditori de oleum-vipera non vigere excordis populi"


 
Comment: The link in the previous posting includes:
Chapter 4
Performance Controller Technology
The Controller performs a number of functions electronically. An explanation of each follows: Energy savings is achieved by means of a closed loop feedback system. The sensing circuits in the Controller compare the voltage and current waveforms at the motor. Because this is an induction circuit, the voltage and current waveforms start at different times. The smaller the load on the motor, the greater the lag in the current waveform. At no load, the motor is least efficient and the waveforms have the largest distance between them. We measure the distance between the two and compare this difference to an operational distance. The difference between the actual waveforms and the ideal is compared and gives us a sum that we call the error voltage. This error voltage is used to create a firing pulse that determines the length of time we send power to the motor. The larger the error voltage, the shorter the firing pulse. The smaller the error voltage, the longer the ‘on’ time of the firing pulses.
In this manner we can regulate the amount of energy that the motor receives to perform it’s work. The speed of the circuit is such that it can change the signal to the motor one hundred twenty times per second (twice the sixty-cycle frequency). This speed is much faster than the motor can operate, and is necessary to keep the motor from stalling under any and all motor functions.

///The principle of the operation is based on the correct theory, engineering and design. How much of actual energy savings will be accomplished depends on a specific application. As stated in other posting, the energy savings may be minimal if a high efficiency motor application to the load is fine tuned. This is usually case where larger motors are applied to loads running continuously, e.g. coolant circulating pumps, certain applications of fans, etc.\\\
 

Sometimes peddlers of “miracle energy-saving” boxes will spit blood denying that their device is based on the Nola-NASA concept. But, jbartos’ excerpted quote is a perfect description of 'wide eyed' or ‘scaled up’ application of the basic device Frank Nola originally conceived for 1ø fractional-hp permanent-split-capacitor consumer-appliance motors in the late 1970s.

 
Thanks for all the info. Looks like we need to do more homework before we jump on board. Thanks again.

 
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