TVSS and Energy Savings?
Copyright © 2004 Francis J. Martino
Below is a note I received from a utility company who found that some of my articles on Transient Voltage Surge Suppressors (TVSS) had been copied and displayed on a TVSS distributor website. My response is also given below. Both of the notes have been revised for clarity and also to protect the guilty and allow the guilty to continue for reasons as noted below.
From the utility:
<< There is a web site that references Frank Martino's publications on TVSS and the protection they provide. This company is operating in our electric company's service territory. This TVSS company references several credible sites on the TVSS products and their benefits. This company, however, are selling their TVSS units and guaranteeing a 20% energy savings. The customers I have worked with have NOT seen this savings, nor do I think they will see it. Could you give me a response with your comments? Thank you. >>
Frank Martino's response:
Thank you for your note.
I have seen no studies of efficiency loss caused by current flow associated with transients.
Normal EMI generated by variable speed drives are similar to transients in frequency and continue over a continuous rather than intermittent time base. EMI loss would therefore be far greater than that of transient loss.
Since losses generated by EMI are insignificant compared to losses generated by the simultaneously generated harmonics, no attention is given in industry to EMI losses from VFDs.
From measurements that I have evaluated, harmonic losses caused by VFDs will normally be a maximum of six percent of fundamental frequency losses, while EMI losses are negligible.
The web page you referenced is by a distributor of the TVSS units and neither the manufacturer’s web page nor that of the distributor offer any studies done with instrumentation.
I could conceive of some energy savings by the reduction of heat caused by transient currents in a Ford assembly plant in which there might be several hundred welders operating both simultaneously and continuously, but I can not image energy savings in a Ford dealership as shown in the photographs on the distributor’s website.
I therefore conclude the following:
1. The "testimonies" of energy savings are from customers who are delusional, except for the owner of the Ford dealership whom, it is reasonable to assume, is the distributor's brother-in-law.
2. Caveat Emptor.
3. Advise your customers to cash in on the guarantee which will refund up to the full amount of the purchase price.
4. I am very tempted to allow the distributor to keep my articles on the web page and then post this note on my web page so that when their customers find my web page in the same manner in which you have done, then they will be spared the pain of being taken for a ride (and not necessarily from the Ford dealership's used car department).
5. You may find to be of interest my article on Skullduggery Afoot.
Have a Happy and Prosperous New Year!