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Power Factor Controllers


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#21 Guest__*

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Posted 25 March 2005 - 11:47 PM

Here's a sample savings analysis from a Somars' Motor Boss dealer. What, if anything, looks wrong about this?

#22 marke

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Posted 26 March 2005 - 10:42 AM

You forgot to Attach the analysis.
Best regards,

#23 jraef

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Posted 14 April 2005 - 01:34 AM

LOL Marke,
Are you sure he forgot it, or was he making his point by not attaching anything??
"He's not dead, he's just pinin' for the fjords!"

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Posted 27 October 2005 - 09:12 PM

I am also interested in the claims of Somars International who were recently bestowed the Queens Award 2004. The website is www.somars.com. The company claims to be different from all other competitors with its intelligent design energy savers. What is your analysis of the claims of energy savings?

#25 jraef

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Posted 28 October 2005 - 07:17 AM

Every one of them claim to be vastly different than all the others, no exceptions. They have all supposedly come up with some new microprocessor solution etc. etc. So if you believe them all, what are they all different than? It is all just marketing. The technology behind what they do is all based on the same basic principles outlined in Mark's paper mentioned at the beginning of this thread.

LOL, the Queen's Award. Last I checked, the Queen was not an Electrical Engineer.
QUOTE
The Queen’s Awards for Enterprise: International Trade 2004
HER MAJESTY THE QUEEN has been graciously pleased to confer Her Awards in 2004 upon the following business units in recognition of their outstanding achievements in International Trade:...

*   Award Categories   *
*  International Trade

Business units must be able to demonstrate substantial growth in overseas earnings and commercial success, to levels that are outstanding for the goods or services concerned and for the size of the applicant's operations. Businesses may apply under the following criteria:

   * Outstanding achievement in international trade, sustained over not less than three years.
     or
   * Continuous achievement in international trade, sustained over not less than six years.
What Somar got in 2004 was not the "Innovation" award, but the "International Trade" award. Getting that award just means they were successful in exporting something from Great Britain. Other winners of that "prestigious" award exported corduroy fabric, magazines and remanufactured ink jet printer cartridges. I doubt that whatever commission hands that award out in the Queen's name has any idea what it is and what it does.
"He's not dead, he's just pinin' for the fjords!"

#26 marke

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Posted 28 October 2005 - 10:15 AM

Yes, I agree, they all claim to have different better technology etc, but at the end of the day, you can only save what is being wasted, and the common denominator is the motor. It is the motor and load characteristics that determine what is being wasted, and this limits how much can be saved. Look at the motor data to determine what can be reality. I have seen so many claims that sve more energy than would be saved if the motor was turned OFF!!
All that I can suggest is that you study the motor efficiency curves and find applicatios where the motors are operating very inefficiently before you try to save any energy.
Do your won tests and make your own decisions on the merits of the claims and the product. If it works well for you, that is great, but do your own tests correctly.
Over sized motors can often run more efficiently than motors at full load!! - don't assume that because a motor is operating at less than full load, it will save significant energy.

Best regards,

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Posted 07 December 2005 - 01:41 PM

:mad:
use VDF in case what can saves;q?
calculator % saves by how?
thankS!

#28 marke

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Posted 07 December 2005 - 05:56 PM

Hi this posting should be in the variable speed section. VFDs reduce the machine speed. This can reduce the mechanical losses and achieve energy savings that way provided that the machine can be slowed down without affecting the useful work done.

Best regards,

#29 cnavlekar

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Posted 13 April 2006 - 06:37 AM

I am NEW commer in the business and have reasonable techinical backround. I have planed to take up energy saver dealership.This forum has given me caution to get in with care.

I am praposing to record power consumption patterns on target machines.Analyse the actual load pattern VS time apply saving % based on theory and estimate ROI then propose instllation to prospective customer.
Does any one have suggestion on the pprocess.

#30 marke

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Posted 13 April 2006 - 06:50 AM

Hello cnavlekar

You are taking the right approach, but unfortunately, there is a lot of work in doing what you plan. DO NOT fall into the trap of measuring volts and/or amps and basing your results on that. The customer pays on the results of a KWHr meter and that is what you need to use. Your supplier may well tell you otherwise, but when it comes to convincing an accountant, you need to show the result on the instrument that he will pay on. You also need to record the On load time as well so that you can ensure that any testing is based on a vailid comparison. This probably requires a chart recorder recording current against time. I would suggest a period of time with the recording equipment in place and no energy saver, and a similar period of time with the energy saver in circuit. Then check that the operating time and the onload time for the two recordings are comparible before comparing the KWHrs used.

It is a lot of work to do it properly. If you dont do it right, the results can be very wrong and you could be proven wrong by a consumer.

Best regards,

#31 cnavlekar

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Posted 13 April 2006 - 08:39 AM

Mark,
Thanks for quick response
I am planning records on power meter connected by com link 485 to SCADA .This will give me every thing kVA,kW,kWh on time scale. What %ge or absolute value saving should I consider for loads below 30% DAWN TO 10% OR SO.

#32 marke

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Posted 13 April 2006 - 08:53 AM

Hello cnavlekar

I would not worry about % savings, the client pays for KWHrs, not %. A small % of a large amount is often better than a high % of a very small amount. With an induction motor, the savings only tend to occur at very low shaft loads, so you could get a good % of next to nothing.
Payback is in KWHrs saved.

Best regards,

#33 marke

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Posted 14 April 2006 - 03:39 AM

Hello cnavlekar

Further to my last post, please ensure that the power meter is suitable for use with a discontinuous sinewave current. Some power meters need to have a clean sinewave curent and/or voltage or the reading will be very inaccurate.

I would do your own tests and verification before signing up and committing to a volume of product or licencing fee.

Best regards,

#34 cnavlekar

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Posted 25 May 2006 - 10:45 AM

QUOTE(marke @ Apr 14 2006, 09:09 AM) View Post

Hello cnavlekar
Further to my last post, please ensure that the power meter is suitable for use with a discontinuous sinewave current. Some power meters need to have a clean sinewave curent and/or voltage or the reading will be very inaccurate.
I would do your own tests and verification before signing up and committing to a volume of product or licencing fee.
Best regards,


Mark,
Thanks again .I understand that theeis one manufactyrer of energy saving in Newziland device for AC motor .Do you know any details?
cnavlekar huh.gif

#35 GGOSS

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Posted 26 May 2006 - 02:22 AM

A look at the following discussion thread might prove useful.

http://www.lmpforum....p?showtopic=507

regards,
GGOSS

#36 marke

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Posted 26 May 2006 - 07:46 AM

Hello cnavlekar

There used to be one made back in the early 80s, I designed it and stopped marketing it for energy savings in the mid 80s to concentrate on soft start only.

I am not aware of any other product manufacturered in New Zealand.

There is a soft starter manufacturer here, AuCom Electronics, but they do not do energy savers.

Best regards,

#37 cnavlekar

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Posted 26 May 2006 - 08:46 AM

QUOTE(marke @ May 26 2006, 01:16 PM) View Post

Hello cnavlekar

There used to be one made back in the early 80s, I designed it and stopped marketing it for energy savings in the mid 80s to concentrate on soft start only.

I am not aware of any other product manufacturered in New Zealand.

There is a soft starter manufacturer here, AuCom Electronics, but they do not do energy savers.

Best regards,

Thanks
I have come accross interesting paper analysing the performance of energy saving by phase control. What is your take on the savings shown on single phase ?Seems real.


Measured efficiency improvements of induction motors with thyristor/triac controllers

Fuchs, E.F. Hanna, W.J.
Dept. of Electr. Eng., Univ. of Colorado, Boulder, CO;

This paper appears in: Energy Conversion, IEEE Transactions on
Publication Date: Dec 2002
Volume: 17, Issue: 4
On page(s): 437- 444
ISSN: 0885-8969
INSPEC Accession Number: 7497847
Digital Object Identifier: 10.1109/TEC.2002.805180
Posted online: 2003-01-06 15:15:06.0




Abstract
The deployment of inexpensive thyristor/triac controllers improves the efficiency and does not increase the power factor of induction motors (as measured at the input of pole transformer) operating under variable torque and constant speed constraints. Computer-aided testing yields detailed input/output powers for the drive. The improvement of the power factor does not increase the real-power capability (RPC) of a transformer supplying power to such drives due to current harmonics. Although the total harmonic current distortion (THD/sub i/) may exceed IEEE 519 and IEC 555 recommendations, publications show that the impact on the apparent power derating of a 25 kVA pole transformer is small if THD/sub i/<50%.


#38 marke

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Posted 26 May 2006 - 07:57 PM

I have not seen this paper, looks interesting. Do you have a link to it??

Best regards,

#39 mariomaggi

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Posted 26 May 2006 - 08:34 PM

Link (not free)

Regards
Mario

Mario Maggi - Italy - http://www.evlist.ithttps://www.axu.it


#40 cnavlekar

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Posted 27 May 2006 - 08:34 AM

QUOTE(marke @ May 27 2006, 01:27 AM) View Post

I have not seen this paper, looks interesting. Do you have a link to it??

Best regards,


I got hard copy from public library .It is available from IEEE Explorer for members price is US $ 13.

cnavlekar




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