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rjns
Illuminated house number

My 1948 house has an illuminated house number that is wired in on the doorbell circuit. Since there's no switch, the bulbs stay on all the time. It takes screw in type E-10 base lamps, but nowadays the bulbs are only rated to last about 30 hours. I want to install a photocell so that it only lights up at night. Anyone ever done this?

Better yet, if anyone knows how to convert it to LED with the photocell?

Re: Illuminated house number
rjns wrote:

My 1948 house has an illuminated house number that is wired in on the doorbell circuit. Since there's no switch, the bulbs stay on all the time. It takes screw in type E-10 base lamps, but nowadays the bulbs are only rated to last about 30 hours. I want to install a photocell so that it only lights up at night. Anyone ever done this?

Better yet, if anyone knows how to convert it to LED with the photocell?

How often do you have to change bulbs?

What voltage are they rated at?

If they're run at reduced voltage you can get much more than their rated life. It might take years to break even, if you install a photocell.

Photocells don't like light loads like LED

rjns
Re: Illuminated house number

Sorry, read the wrong label. The ones I have last about 1000 hours, not 30, but running 24hrs/day will last almost 2 months. They are #50 miniature lamps, 7.5V, 220mA. Since these bulbs can be used in flashlights and auto lights, which are DC, I'm considering just throwing some LED's in there. I know they'll flash, but it should be faster than the eye can detect based on 60Hz. And even if they only last 50000 hours instead of the usual 100000, I'd only have to change them every 5-6 years instead of every 2 months. Hopefully this works.

Plus, I'd rather not use a photocell now. The frame is brass and I'd have to drill a hole in it for the face of the photocell. But if the LED's don't work, I may have to revisit this. I thought photocells only cost a couple of dollars? The ones used in night lights and such.

Re: Illuminated house number
rjns wrote:

Sorry, read the wrong label. The ones I have last about 1000 hours, not 30, but running 24hrs/day will last almost 2 months. They are #50 miniature lamps, 7.5V, 220mA. Since these bulbs can be used in flashlights and auto lights, which are DC, I'm considering just throwing some LED's in there. I know they'll flash, but it should be faster than the eye can detect based on 60Hz. And even if they only last 50000 hours instead of the usual 100000, I'd only have to change them every 5-6 years instead of every 2 months. Hopefully this works.

Plus, I'd rather not use a photocell now. The frame is brass and I'd have to drill a hole in it for the face of the photocell. But if the LED's don't work, I may have to revisit this. I thought photocells only cost a couple of dollars? The ones used in night lights and such.

If the (50) incandescent lamps are rated 7.5 V and you're running them off a doorbell transformer at 14 V ac, it might explain why they're burning out too soon. If you could run them at 6V AC they would last forever.

LED's are DC devices and are polarity sensitive so, if you want LED's you will need to run them off a DC power supply. I also noticed they cost about $8 each. Some $$ invoved.

rjns
Re: Illuminated house number

I did also get some 14.4V bulbs, but they only last 30 hours. I have no idea how to reduce the voltage any further without replacing the transformer, which would involve opening up the wall.

I understand that using LED's with AC will reduce their life, but again, even if they only last half of their rated hours and at $8/each, that would be $16 every 5 years (light uses 2 bulbs) as opposed to $4 every 2-3 months.

I'm trying to find a multimeter to actually check what the voltage is. It may be less than 14V.

Maybe I'll just have to keep one bulb in there at a time, but I'm going to keep digging for now.

Thanks for the input!

William
Re: Illuminated house number
rjns wrote:

Plus, I'd rather not use a photocell now. The frame is brass and I'd have to drill a hole in it for the face of the photocell. But if the LED's don't work, I may have to revisit this. I thought photocells only cost a couple of dollars? The ones used in night lights and such.

How old is that transformer? If it's as old as the house then it might be time to replace it with a 6 volt as Semi-Retired Electric suggested. If the same transformer goes to your doorbell then simply get a wireless doorbell. Much cheaper than constantly replacing bulbs every 30 hours.

Also, why not just get a solar powered illuminated house number like THIS one?

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