V Phase

I saw some posts about this last year and last night on DIY SOS they fitted this device to the new consumer unit being fitted to the house being 'done up'. This was at the suggestion of some 'green' guru who was consulting on all aspects of the build including insulation etc. Has anyone got one installed? Saved any money? For the un-aware take a look here:

formatting link
a FAQ here:
formatting link

Reply to
Dr Hfuhruhurr
Loading thread data ...

Reducing voltage will reduce the current that resistive loads (e.g. immersion or storage heaters) take, but if the appliance is controlled by a thermostat it will run for longer to reach the required temperature.

For equipment with switched mode power supplies, lowering the peak of the A/C waveform will just tempt the PSU to draw power for a greater fraction of each 50Hz cycle.

In short not likely to save much ...

Reply to
Andy Burns

Oh yes ... will also dim incandescent bulbs (by a greater factor than the cost saving) but probably not affect CFL or halogens on electronic transformers.

Reply to
Andy Burns

There was a VPhase rep in my local wholesalers last week.

He claimed that the VPhase will give GU10 lamps an extended life due to the lower voltage when they are switched on.

Reply to
ARWadsworth

Sounds feasible, though I'd think the lower voltage while running would also be a factor rather than just the switch on surge

240V dropped to 220V is about an 8.3% cut, for about a 23% cut in light output.
Reply to
Andy Burns

It will indeed. And of course reduce efficiency. So less light from the electricity they use.

In general, the cost of the lamp itself is a fraction of the cost of the electricity it uses in its lifetime. So better to fit a smaller lamp. In practice, most 50w GU10 types can be replaced with 35w without anyone noticing - unless they are side by side. Low voltage 50w with 20w.

If you have an awkward to change one and the light output isn't too important stick a diode in series. That will extend the life greatly.

Reply to
Dave Plowman (News)

I used to do that with mains xmas tree series chains, diode in the 13A plug. I have at least one set still going that is 25 or 30 years old. Two further advantages are the brightness is reduced to a more appropriate level (these things always seem to be designed to over-run) and I perceive a pleasing 25Hz flicker.

Reply to
Graham.

As has ben said before, there are ways to shave a few pennies off electricity use, but none suit all appliances, there's no single cure- all.

NT

Reply to
Tabby

here:

formatting link
> and a FAQ here:
formatting link
>>> Ta

Presumably this is little more than a 15v high current transformer wired in anti-phase with the supply?

Bob

Reply to
Bob Minchin

What does "wired in anti-phase with the supply" mean?

Reply to
Dave Osborne

Wired such that the low voltage subtracts from the incoming supply. Actually the voltage would need to be more like 25v not 15v - my mistake

Bob

Reply to
Bob Minchin

Forgive me being obtuse; I'm still not with you. How would you wire the transformer and the load such that "the low voltage subtracts from the incoming supply"?

Thanks.

Reply to
Dave Osborne

I'd assume like this

formatting link
FAQ pdf that was posted earlier shows a "large pork pie" sized toroidal transformer in the unit ...

Reply to
Andy Burns

I have drawn a diagram here

formatting link
that the secondary must be able to carry the maximum current to be drawn from the output.

Hope this helps Bob

Reply to
Bob Minchin

Many, many moons ago I bought a switched & indicated plug for my 15W soldering iron. Soldering a diode across the switch gave me a 2-heat iron. Just hot enough to melt 60/40 solder on "cool" and quick to heat up to full. The neon also dims to show when the iron is on "cool".

Reply to
mick

OK, so this is an ersatz form of autotransformer. I've not come across this technique before.

I say ersatz because there is no guarantee that the insulation on the secondary wiring (of any given transformer not designed for this purpose) is rated or proof tested for mains voltage operation.

The idea that confused me intially was the "anti-phase" bit. I suppose you would say that if you connected the secondary winding the other way round, it would be "in phase" and boost the 240V to 260V.

Cheers, DaveyOz

Reply to
Dave Osborne

Google autotransformer..

Reply to
The Natural Philosopher

If you use a standard modern plastic bobbin transformer, insulation wont be an issue.

NT

Reply to
Tabby

If you use an autotransformer, its less copper and it doesn' matter a damn because there is no secondary..

Reply to
The Natural Philosopher

here:

formatting link
and a FAQ here:
formatting link
> Ta

Ever heard the expression `brown-out` thats what these create deliberately ,usually an autotransformer.

In large buildings if you wanted 220V you could get the power tapped down so with these substantial savings why aren`t they?

15% less power to incandescent rated to 240/250 use is going to be dim, very dim, more than15% dimmer meaning savings are mythical.

Mag ballasted lights will not like the lower voltage and will pull more current probably losing efficiency to heat, another myth bites it.

Motors, Ohms law means lower voltage will draw more current for same work done, meaning possibly higher heat losses, you canna change the laws of physics Cap`n...

Motors and ballasts are 2 things can think of that may have seoerate taps for 220 and 240V

It isn`t a new idea, and it still isn`t a good one.

Cheers Adam

Reply to
Adam Aglionby

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.