Re: Cost of electricity for light dimmer

From: Sylvia Else (sylvia_at_not.at.this.address)
Date: 10/27/04 

Date: Thu, 28 Oct 2004 09:02:53 +1000

phil-news-nospam@ipal.net wrote:

> In alt.engineering.electrical Sylvia Else <sylvia@not.at.this.address> wrote:
>
> | This in particular is why you shouldn't use dimmers with lamps that are
> | mounted so that the filament is above the socket. When such lamps burn
> | out it is not uncommon for a broken piece of filament to fall and
> | briefly short across the two thick wires that feed the ends of the filament.
>
> I had one bulb do that in a non-brief way, once. The filament shorted
> in such a way that it had about 75% if it's length still working. It
> got brighter (in theory, from 60 watts to 80 watts if that estimate of
> filament length was correct. The nice thing was the light now looked
> a lot more "white". Unfortunately it gave out about a week later.
>
> Someone once suggested getting 100 volt (because that is their nominal
> voltage) light bulbs intended for the Japanese domestic market. That
> would get a brighter whiter light. Just be sure to get a lot of them
> as you will be changing bulbs more frequently. A 60 watt 100 volt bulb
> run on 120 volts will be dissipating about 86 watts (NOT figuring in the
> change of resistance due to the change of heat). Which could be used in
> place of a 100 watt bulb. Power usage goes up. Light output goes up even
> more. Bulb replacement goes up, too.
>
> Other people prefer bulbs rated for 130 volts so they don't have to change
> them so often. In hard to reach places that's definitely a plus.
>

There was some correspondence in New Scientists about the impact of
mains overvoltages on the life of incandescent lamps. Something along
the lines of a 10% overvoltage halves the life.

It's just possible that the lamp manufacturers really have chosen an
operating point that represents the best choice for the majority of people.

I use flourescent substitutes in some places, but they're not exactly a
perfect solution either. The ones I use take a significant time
(minutes, I think) to reach their peak brightness, an effect that seems
to get worse as they age. However I've yet to have to replace one.

I don't know that you can use a dimmer with them, though. I rather
suspect they wouldn't like that.

Sylvia.

Relevant Pages

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