For a paper on the power factor controller energy savers (Based on a NASA algorithm) have a look at http://www.lmphotonics.com/energy.htm
The technology works, but it well over stated and over sold.

I have read your paper with interest. I work for a company who sell such controllers.

A lot of your comments are unduly negative, however I do agree that in the general marketplace I have seen some of our competitors sell controllers and fit them to any old application and mislead the savings made.

We have one of the only controllers on the market (Globally) that can control succesfully (for example) Injection moudling machines where it is common to go from 20kw off load to 150kw full load within 1/150th of a second. We have hundreds of blue chip companies as customers, and Jaguar have hundreds of our units on site.

I would wholly appreciate you re-writing the report, and place positive aspects of motor controllers also to create a balanced view as your opinions are somewhat biased for some reason.

We have had scores of independant tests done on our product which show undoubtedly the savings made which include thermal imaging on motors with & without our product, and we have the only product that is truly intelligent.

I am the first to agree, we have some poor quality competition in the market and we are doing our best GLOBALLY to promote a truly unique and world class device as our own.

I look forward to your reply.

Hello Sienna
I am sorry that you find the report so negative. In my book, the bottom line is that You Can only save PART of the energy that is being WASTED. If the motor is operating well below its maximum efficiency for significant periods of time, energy can be saved. There is no argument about that, and that is clearly stated. My negativity is towards some of the claims made in the market place. I do clearly state that the technology works. If you have any particular areas of the report that you have problems with, perhaps you could let me know.
:)

C'mon Siena ...surely you must admit that there are very few loads that will benefit from so-called energy savers .

Yes, the Intermittent loads where power consumption jumps from zero to full load in a fraction of a second is one of them .

But you could also argue that even in installations where these loads predominate ......you may be better off economically putting in some fast acting Thyristor PF. correction which will then control the total PF of the plant or section of the plant .....as opposed to at individual motors.

I am pretty sure that it would be cheaper (for example ) to put one common PF controller to correct lets say 10x 55kW motors operating intermttently ............than to install 10 ...Soft Starts with energy saving .......and it seems that if you need to go from no-load to full in 150th of a sec ......then you hardly need a Soft start.

If you have a Motor that runs for long periods unloaded ......then perhaps it is better to use the best energy saver of all ........switch it off.

I get the distinct feeling from talking to R+D people in Starter manufacturing companies that they include is feature mainly so that are not the odd men out .........rather than because it is a useful feature.

Hi Siena,

I must say that I fully agree with most comments made by both Mark and Harry on this subject......but I am also prepared to give you the benefit of the doubt.

Unfortunately my experience with people marketing such products is that when they are asked the 'hard questions' they do not respond by providing proof of their claims. In fact most simply don't respond at all!

You appear to be very passionate about this subject and you have also made comment about other lesser products currently available on the world market.

I am providing you with an opportunity to establish some credibility and tell the forum why your product out-performs all others. Please ensure that you support any claims with technical facts.

Looking forward to your reply.

GGOSS

;)

Thank you all for your comments.

I will provide independant technical test reports of our product, by I will need an E-mail address to send them to. I will also next week send details of the Thermal Imaging tests we performed.

Replies to each person now!!

To GGOSS

>>Unfortunately my experience with people marketing such products is that when they are asked the 'hard questions' they do not respond by providing proof of their claims. In fact most simply don't respond at all!<<

I have seen it a lot, its generally because they are poorly trained or are just looking at the wrong applications or trying to make a fast buck.

To Harry Dampers,
>>C'mon Siena ...surely you must admit that there are very few loads that will benefit from so-called energy savers<<

No, there are thousands of applications worldwide. In our company experience the "Best" ones are Injection moulding machines (we have an approval from Mannesman Demag!!) Granulators, Crushers, Compressors, Vac Pumps and anything else that has a motor overated for the job of work its doing.

>>But you could also argue that even in installations where these loads predominate ......you may be better off economically putting in some fast acting Thyristor PF. correction which will then control the total PF of the plant or section of the plant .....as opposed to at individual motors.<<

Yes, you could argue that but you still have no control over the motors. It is common to install a controller where the site already has PF correction.


>>I am pretty sure that it would be cheaper (for example ) to put one common PF controller to correct lets say 10x 55kW motors operating intermttently ............than to install 10 ...Soft Starts with energy saving .......and it seems that if you need to go from no-load to full in 150th of a sec ......then you hardly need a Soft start<<

What happens under Star Delta starting?? upto 20 times initial running current is pulled into the motor. I have seen drive trains sheared because of this. We can also soft start any torque changes in the motor if required, this is particularly useful on compressors with large accumulators fitted. This significantly prolongs the life of the system. If the motors you suggest were operating intermittently then i would agree with you, ther would not be a significant return on investment. Ideally for our product you need a motor to run at least 18 hours per day & 5 days per week. We do however look for 24/7 applications.

>>If you have a Motor that runs for long periods unloaded ......then perhaps it is better to use the best energy saver of all ........switch it off.<<

Our unit can be set up to switch off the motor automatically after a pre-determined period of no load. I have been to thousands of factories where motors are just running for no reason.

>>I get the distinct feeling from talking to R+D people in Starter manufacturing companies that they include is feature mainly so that are not the odd men out .........rather than because it is a useful feature.<<

We sell Soft Starters under 7.5kw and mention any energy saving will be a bonus. However, 11kw upto 900kw are sold as pure energy saving devices with a whole host of additional benefits.


I have writers cramp now!!, if someone can indicate which E-mail address they would like further information on our product I will gladly send it next week. I am out of the office Thursday & Friday.

With Kind Regards

I for one would be interested in seeing any information that you have. My email address is empson (at) lmphotonics (dot) com
;e

I think that perhaps the point of most interest here, is not whether the technology can save energy under the right conditions, that is not in dispute, but can the energy saved jsutify the expense in terms of money saved and the cost of saving it. Would you spend $1000 to save $10 per year?? you may be better to put the $1000 in the bank and earn interest!
;q

[Edited on 4/7/02 by marke]

[Edited on 4/7/02 by marke]

Hello Sienna,

In previous posts you have stated that it is the technology used in your product that makes it a much more affective energy saving device than others presently available on the world market.

Without revealing any 'trade secrets' can you enlighten us further on the technology being used and how the product operates in a 'real world' applications?

I am interested to know more, as are other members of this forum.

Regards,
GGOSS

I would like to summarise the data that I was submitted as follows.
Tests done on a 15KW motor.
At full load (15KW), the power consumed was 18.57 KW.
At half load, (8.9 KW) power input was 11.44 KW.
At no load (0.4Kw) the power input was 8.3KW.

Savings at half load were about 1KW (9.71%) and at no load the savings were about 3.5KW (41%)

The problem that I have with these results is:
At full load, the total losses are in the order of 3.5KW, and at half load, about 2.5kw and at no load, the total losses were a whopping great 7.9KW

My understanding of induction motors shows that the iron loss is essentially constant (independant of load) and the copper loss is dependant on the current squared. I would expect that the iron and copper loss at full load are in the same order of magnitude and constitute the greatest proprtion of the lotal losses. I am unable to see why the energy wasted at no load is so much higher than at full load or at half load. In this case, I would expect that the no load energy losses would be more like 2 KW, and assuming that the quoted percentage saving was correct at about 38%, this would result in an energy saving of about 760W. What is the pay back period??

I have been looking for a mechanism for the increased losses at no load, but to date, none has been forthcoming.
Any thoughts??
;q

I agree with you Mark. The 8KW loss at no-load is not realistic.

#1 - There is no physical basis for explaining rapidly increasing losses as power decreases.

#2 - If the motor is sized to handle 8kw of losses but has only 3kw at full load, then shouldn't the motor rating be much higher? Simply doesn't make sense.

#3 - I have reviewed motor test data and never seen any results similar to this.

Dear Sienna,

I would appreciate it very much if you can inform me about the website or contact information for the company which sells Power Factor Controllers that you work for (you have mentioned ()

Yours sincerely
Gokalp



[Edited on 9/11/02 by marke]

Hi Sienna,

I love to get more detail about your product which make great energy saving on induction motors.

Thanks
CSS

Hi Sienna,

Need more detail about your product which make great energy saving on induction motors. How it work ?
any website ?

Thanks

Dear Marke,

I am currently dealing with the same question for our company and I am very interesseted in the results of Siennas example.

I am not an expert in this issue, but I am missing one thing in all posts that I have seen so far (also in other forums): The distinguishing between active power (kW) and reactive power (kVAr).

Is seems to be undoubted, that energy can be saved with a soft starter. I think (almost) everybody will agree to this statement. The question is only: How much and what is the benefit?

In my opinion, the most part of the power that can be saved with a soft starter is reactive power (kVAr). In our case (and maybe also for many other customers), this is not interesting, as we do have power factor compensation units installed that are suitable to compensate to almost 0.99. So the saving in kVAr that might be achieved is not interesting. More interseting for me is the savings in active power (kW), because that is for me the real benefit.

Therefore it would be interesting to know, what is that part in the example of Sienna? I think that the savings that you mentioned in your last post is not 8.3kW for 0% load, but 8.3 kVA. I assume that most of this 8.3kVA is kVAr and therefore not really intersting for many customers.

;p;