How to power a h7 bulb from 110v?

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I have the inside of an old headlight housing that i am trying to make a lamp from. I want to use the headlight bulb as the bulb in the lamp. How can i cheaply power the 12v headlight from 120v wall power? Also I imagine if i give the headlight the full 100w of power it will be to bright?

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You'll just need a 12v 5a power supply (minimum) but you'll be running it at full capacity so its going to make some heat. My recommendation would be to repurpose an ATX power supply from a computer. It should have the capacity, and will be fan cooled.
 
Can you retrofit another bulb into the base of an H7 bulb? Im thinking something with a candelabra base, so its small, and then just wire up 120 to the back of it.

How critical is it to have the automotive bulb be in there? I see its a reflector, so hot spot location is somewhat important, but to what extent?

Since youre not driving with it in a lamp, Id look at the LED H7 options. Even if illegal and slightly different beam pattern, it will likely drop your power requirements and heat load to 35W or so, which might make things easier.
 
Originally Posted by doitmyself
100 watts at 12 volts is about 8.3 amps. Would it be best to search for a "12 volt 10 amp power supply"????? Or, am I missing something here.


Since when is a (legal) H7 bulb 100W?
 
Originally Posted by JHZR2
Originally Posted by doitmyself
100 watts at 12 volts is about 8.3 amps. Would it be best to search for a "12 volt 10 amp power supply"????? Or, am I missing something here.


Since when is a (legal) H7 bulb 100W?

My bad it's actually 55w
 
Originally Posted by JHZR2
Can you retrofit another bulb into the base of an H7 bulb? Im thinking something with a candelabra base, so its small, and then just wire up 120 to the back of it.

How critical is it to have the automotive bulb be in there? I see its a reflector, so hot spot location is somewhat important, but to what extent?

Since youre not driving with it in a lamp, Id look at the LED H7 options. Even if illegal and slightly different beam pattern, it will likely drop your power requirements and heat load to 35W or so, which might make things easier.

I think having an automotive bulb would be cool but my main issue was I could not find another 110v bulb to fit into the opening as its only 20mm wide.
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There have been conversions to h11 bulbs, which supposedly have better output. There are adapters. Looks like a bosch or hella projector out of an older Audi.
 
You need a 110V to 12.6 volt step-down transformer.

Try this company, its 12.6 volts 5A or 60 VA.

https://www.parts-express.com/12v-ct-5a-power-transformer-(63v-0-63v)--120-205?gclid=EAIaIQobChMIsdiZjd-M6QIVhYbACh3g9gMrEAQYBCABEgLoCvD_BwE
 
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Originally Posted by joegreen
Originally Posted by JHZR2
Can you retrofit another bulb into the base of an H7 bulb? Im thinking something with a candelabra base, so its small, and then just wire up 120 to the back of it.

How critical is it to have the automotive bulb be in there? I see its a reflector, so hot spot location is somewhat important, but to what extent?

Since youre not driving with it in a lamp, Id look at the LED H7 options. Even if illegal and slightly different beam pattern, it will likely drop your power requirements and heat load to 35W or so, which might make things easier.

I think having an automotive bulb would be cool but my main issue was I could not find another 110v bulb to fit into the opening as its only 20mm wide.



What I'm saying is to use the base of an H7 (capsule, element, electrical connections removed) to retrofit a Female candelabra base bulb (screw in but much smaller than a standard light bulb socket to it.
 
A relatively common antique dumb 12 volt battery charger will run it, just make sure it's 10amp+

Should be cheaper than many other options.
 
Looks lie a fire hazard waiting to happen from either lamp heat or PS overheating.

My Mother almost burnt the house down a couple times with those

halogen reading lamps that were popular in the 80's

But it reads like you just want to run the lens.

So, a cheap flash light LED cluster and a current limiting resistor and an appropriate wall wart.

Here is your chance to research and study instead of asking
smile.gif
 
Inrush current is the main problem. When cold an h7 can draw 15 or 20 amps, then only 6 when running (assuming 65 watt)

Also they emit UV and you can get sunburn from them.

use a led conversion H7.

Rod
 
Originally Posted by ctechbob
You'll just need a 12v 5a power supply (minimum) but you'll be running it at full capacity so its going to make some heat. My recommendation would be to repurpose an ATX power supply from a computer. It should have the capacity, and will be fan cooled.


+1
 
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