How much power does a 120v 15A lighted switch use anyway?

[Glenda Copeland]

What is a wall wart?

[Glenda Copeland]

I don't understand the 1/100th the percentage (figure 98% of the time the switch is off so the neon bulb is on).

What's the 1/100 for?

[Glenda Copeland]

It looks like it's costing 25¢/month for the dozen neon-lit switches.

What noise would I be worried about? I have the normal stuff (phones, computer, router, etc.) Which would the neon affect and how?

BTW, I didn't see ANY LED illuminated switches at ACE or OSH in town! :(

[Glenda Copeland]

Using 0.1W, and averaging my electric rates (35¢/KW) for a dozen switches I get about 25¢/month or $3.00/year.

[Glenda Copeland]

Yes.

The only "problem" is that our energy here in sunny California is nowhere near 10¢ per KWh. I'm going to get my bill and come back with the actual numbers, but the first KWh is about 12¢ but that only lasts for a "baseline" which is about a week. Then the next week is double, then triple, then more than four times that when you get to the last week.

I'm figuring easily that it's 35¢/KWh here in California. Any other Californians out there that can help me on the math?

My math comes to about $3.00/year for the dozen switches.

[Glenda Copeland]

You guys have cheap electricity!

I just pulled out my California PG&E bill to check the numbers (I can't believe you guys pay only a dime per Kwh!!!!!. Lucky you!)

My baseline is 365.4Kwh at 12¢/Kwh Then for 101% to 130% of baseline, it's 14¢/Kwh. For 131% to 200%, it's 29¢/Kwh. And, for the last few weeks of the month, at 201% to 300% of baseline, it's

43¢/month.

I averaged this to about 35¢/Kwh because I didn't know how to do the math otherwise (I used over 150 Kwh at the 131% to 200% rate and 256 Kwh at the

29¢ rate).

.1W/bulb x 12switches x 20hours/day x 365days/year x 35¢/Kwh x 1Kwh/1000KW = $3.00/year

It would be nice to see what others pay for 201% to 300% over baseline 'cuz if it's 10¢, you have the deal of the century!

[Nonny]

Interesting observation. I know that when a single lead from a neon light touches a hot wire, the neon light will glow if there is almost anything touching the other lead. Was used as a voltage checker long before the IC devices were available. If the neon's lead was touching a hot wire and the other a ground/neutral, then the lamp glowed brightly, otherwise, there was a lesser glow.

This leads me to the conclusion that neon lighted switches take advantage of this ability and do NOT require a lead to ground or neutral to achieve the low level glow seen in a lighted switch. Perhaps an LED lighted switch would require a grounded/neutral other lead to work, together with diode to convert the AC to DC.

[chaniarts]

in our area, the rate during the day is 2x the rate for nighttime or weekends, so we try to schedule our heavy usage for off peak. nighttime rates are in the .07kwh range.

i run a couple of kilns, at about 8kh each, which can run for 2-3 days straight, so i couldn't afford to live in ca.

however, i just installed a 7.5kw pv cell array, so my day costs are 0.

[jeff_wisnia]

I don't think so. IIRC an ionized neon bulb requires about 60 volts across it, close to half of a 120 volt line voltage.

And I don't think the "typical" series resistor is 1 meg. 50K to 100K is more like it.

Jeff

[keith]

$.10, top to bottom, Winter and Summer (heat pump).

[keith]

AM radio, close to the lamp tuned to a very weak station, maybe.

[keith]

Power supply (AC or DC) that plugs into the wall and has a cord that attaches to an electronic gadget. It's a bump on the wall, hence "wall wart".

[David Nebenzahl]

On 5/18/2010 10:11 AM Glenda Copeland spake thus:

Yeah, Don, what's up with that? Nothing more annoying than unexplained "adjustments" like that.

[Rod Speed]

Nope, you have very expensive electricity.

You should be using the highest rate you actually get charged, because that is what you get charged for the extra electricity those switches use.

That conflicts with the previous para listing the rates unless that para is badly worded, particularly with the weeks bit.

If there is no week effect, just the charge that varys with the percentage of what you call the baseline, you should use the charge for the highest band you actually pay which will either be 28c or 43c

Thats hardly a shocking charge that will send you bankrupt any time soon even at the 43c rate.

We have the reverse type of charging, the rate drops the more you use.

Nope, its not that unusual when it comes from hydro.

[Mark]

(- Hide quoted text -

there is NO significant RF noise radiated or conducted at all from a tiny NE-2 neon lamp.. Note, we are NOT talking about neon store window signs that operate at

25kV.

Mark

[HeyBub]

It's gonna get more expensive soon. Arizona provides about 30% of California's power, and Arizona is pissed.

[terry]

Ok on all those numbers but the spec I found showed each neon indicator using about 0.04 watts per hour.

Based on 0.3 milliamps at 115 volts. Thus wattage =3D current times voltage or (0.3 x 115)/1000 =3D 0.0345 watts per hour.

Per month that would be 24 x30 x 0.0345 =3D 24.84 watt/hours.

And at ten cents per 1000 watt hours (i.e. per kilowatt/hour) that'd cost 24.84/1000 x $0.1 =3D approx 0.25 cents At 35 cents per kilowatt hour it would be 0.75 cents, per month. And for a dozen switches 0.75 x 12 =3D about 3 cents or of the order of

36 cents per year. Since we are all presuming, it seems, that the indicator light inside the switches will be off whenever whatever the switch controls is 'on' the indicators will cost even less than that. In other words if one is using electric lights, negligible!

[keith]

99% is defined as 99 times 1/100.

[keith]

:(- Hide quoted text -

There *is* noise caused by the neon firing. Whether you think it is significant or not is simply a judgment.

[keith]

Just a nitpick, but .04 watts per hour is meaningless. It's .04 watt- hours per hour, or just .04 watts. One watt for one hour is defined to be one watt-hour.

No, it's .04 watts (if that's the number). You can't do some arithmetic, throwing away precision, and then come back to the same units with a different number. In this case you lost energy. At least you could have made a perpetual motion machine. ;-)

If one is using other appliances, such as refrigerators, water heaters, or clothes dryers, the lights themselves are (usually) negligible (if not, the whole bill is ;-).