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Watt Guard - Watt is it?

Watt Guard - Watt is it?

Watt Guard - Watt is it?

(OP)
I read about Watt Guard in a local paper. It is used to save energy in large flourescent tube light installations. It does so by 'reducing voltage and thereby increase density of the neon gas and increasing the speed of the electrons 20 000 to 30 000 times'

The latest snake oil, obviously. Some kind of Nolan thing? Anyone heard about this or even tested it? Details?

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

News to me - but if you assume 50Hz supply and a piece of equipment that does nothing special, "increasing the speed of the electrons 20 000 to 30 000 times" might just be another way of saying that it seldom survives the first five minutes of service.

A.

RE: Watt Guard - Watt is it?

The first thing to do would be to update the facility from old magnetic ballasts to more efficient high frequency electronic ballasts. The tubes would be replaced at the same time (often from 40W to 34W). This provides a guaranteed payback period and can typically be financed at zero net cost in the short term and significant savings in the long term. It's a "no brainer".

Once that's done, then you can't use the WattGuard ("Wattguard does not work with self-regulating high-frequency ballasts."). The above approach therefore solves two problems at once: saves money, energy and the planet, and it avoids the temptation of what is likely to be snake oil.

RE: Watt Guard - Watt is it?

(OP)
Thanks! I wasn't aware of that. Thought it was an American or Chinese company.

Will absolutely do that. I have a friend in that region. He needs some publicity. A very good idea to pull their pants down in public. That will make him a hero.  

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

Ooh, watch out Gunnar!

If they're anything like their American energy-scam counterparts, they have a machine gun loaded with attorneys and their finger is on the trigger.

Imagine trying to convince a jury of 12 non-engineers, plus a judge and a gaggle of lawyers, that some magical new thing doesn't work...

Step cautiously, but I'd love to see the pants-down-in-public thing happen!!!

Good on ya and best of luck,

Goober Dave

RE: Watt Guard - Watt is it?

(OP)
I have just finished a test in my lab. Their claim is that they can run the fixtures at a lower voltage. And that that also reduces power. That is true. But they also claim that light intensity is not affected by the lower voltage. That is not true.

I have set up a variac and a 36 W flourescent tube with magnetic ballast. I put a photo transistor in a fixed position pependicular to, and touching, the tube's surface. I took the photo current through a 2x330 ohms resistor and got a 100 Hz pulsating light signal. We have a 50 Hz grid.

I recorded Voltage, current and light signal in one diagram and varied voltage from 0 V to around 265 V (upper tolerance limit for our grid is 253 V)

I am working with the recording and will show a pdf later. The preliminary result is that light output varies with voltage. That was expected.

I think that the trick is to reduce voltage around one percent each day. That will not be noticed. But after some time, you are down to 190 V and lower energy consumption and those that think that they see a difference will probably be given a PC treatment. "Are you against CO2 reduction?" and similar arguments.

It would be equally effective to disconnect 20 - 30 percent of the fixtures.

One positive thing that I can't deny is that lamp life probably will be longer.

Stand by!

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

Sooo, watts up with the gizmo then?

Mike McCann
MMC Engineering

 

RE: Watt Guard - Watt is it?

(OP)
I haven't been able to measure on the device as such. But there cannot be any special waveforms involved - and I don't think that would help much. The reason there can't be any special waveforms is simply that they wouldn't be very effective when you have an inductive (magnetic) ballast. And definitely not with PFC capacitors present.

My guess, without having seen the device IRL, is that they have a programmed dimmer and that the voltage is decreased graduallly over a week or two so that nobody notices how the light level is decreased and then the light stays at the lower level. The low level can, for instance, correspond to the near end-of-life light level of the lamp. That level is still acceptable and since lamp life is prolonged, you have - in fact - an improved situation.

What I do not like is that gas density and 20 000 to 30 000 times faster electrons crap.

A test with a luxmeter will reveal that 'trick' immediately and such measurements are made routinely in workplaces. Don't know about sport centers.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

(OP)
Strange math. In your reference, there are numbers given for power reduction. They are:

37%   power reduction results in 41,5% increase in luminous efficiency
47,5% power reduction results in 43%   increase in luminous efficiency
71%   power reduction results in 82,5% increase in luminous efficiency

I am not sure how many ways you can calculate increase in luminous efficiency. But, if light output stays constant, which I highly doubt, then the numbers should be like this:

37%   power reduction results in  59% increase in luminous efficiency
47,5% power reduction results in  90% increase in luminous efficiency
71%   power reduction results in 345% increase in luminous efficiency

Smells and tastes like snake oil. Flourescent tubes are old hat. Competition has refined the technology for at least five decades. How can it be then that a small, unknown company can demonstrate such dramatic numbers? Too good to be true? Probably.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

(OP)
Strange math, yes. But my math is even stranger. I'll try and get that right:

37%   power reduction results in  59% increase in luminous efficiency
41,5% power reduction results in  71% increase in luminous efficiency
47,5% power reduction results in  90% increase in luminous efficiency

That's better. Well, I mean worse, but more realistic. There was an 'avalanche effect' in the numbers in the 25 Jul 11 4:10 post.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

(OP)
Everything is not snake oil!

I think that I have been too suspicious. That gizmo seems to work! I have added an appendix to the previous report. I took the data into an Excel sheet and plotted power and light output as voltage was taken from seious overvoltage, via rated voltage down to the voltage delivered by the device and then down to extinction.

There is a sweet spot at around 190 V where light/power is 30 - 35 percent better than at rated voltage.

So, if you can tolerate a lower overall light level, the savings are twofold: Better efficiency and lower power input - threefold if you also count longer lamp life (and fourfold if you also count reduced cost for labour).

Read the appendix in http://gke.org/pub/files/Flourescent%20light%20fixtures%20and%20variable%20voltage%20w%20appendix.pdf

I apologize. If they hadn't mentioned denser gas and electron velocity 20 000 to 30 000 times higher! And if they hadn't been saying that light levels are unaffected!!

That - if anything - is snake oil salesmanship. A more honest and fact based marketing and this may very well be a success in many applications.

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

RE: Watt Guard - Watt is it?

So, if you energize a 230 Volt ballast with 190 Volts there is a significant increase in efficiency.
You you get the same results if a 278 Volt ballast were energized from 230 Volts?
I wonder if the manufacturers of ballasts realize that a few extra turns on the primary of the ballast will result in increased efficiency?

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Watt Guard - Watt is it?

(OP)
There must be someone from lighting industry around! There must be lots of knowledge available. Anyone?

Gunnar Englund
www.gke.org
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

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