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Wayne Roberts
Wayne Roberts, Electrical Technician
Category: Electrical
Satisfied Customers: 81
Experience:  Electrican 6+ years
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I need to light a 12V incandescent bulb. what`s the smallest

Customer Question

I need to light a 12V incandescent bulb. what`s the smallest battery I
can use? I tried an A23 12V battery but it doesn`t work.
Submitted: 11 months ago.
Category: Electrical
Expert:  Wayne Roberts replied 11 months ago.

Hello sir, my name is ***** ***** I would love to help, to answer your question we would need the wattage of the bulb.

Customer: replied 11 months ago.
25w
Expert:  Wayne Roberts replied 11 months ago.

you must achieve at least 2 amps for the bulb to work. There are 12v battery options with the required amperage available for a single battery to be used, or you can use multiple smaller batteries to do the same work..like in a flashlight..

Customer: replied 11 months ago.
I know there are 12V battery options I can use. I need to know the smallest battery that will light the bulb.
Expert:  Wayne Roberts replied 11 months ago.

however the bulb should light, even if very dim, with considerably less than 2 amps

Expert:  Wayne Roberts replied 11 months ago.

are you expecting the bulb to light to full brightness? or just to begin to glow?

Customer: replied 11 months ago.
It doesn't have to be full brightness, maybe half.
Expert:  Wayne Roberts replied 11 months ago.

another consideration is how long you would light it to work?

Expert:  Wayne Roberts replied 11 months ago.

like it to work*

Customer: replied 11 months ago.
Just a few minutes would be fine.
Expert:  Wayne Roberts replied 11 months ago.

Something like this would light the bulb for about 15 minutes at full brightness and 30 ish minutes at half brightness.

Expert:  Wayne Roberts replied 11 months ago.

and its rechargeable :)

Expert:  Wayne Roberts replied 11 months ago.

finally, incandescent bulbs efficiency goes down at lower temperatures. So, even though you are using less total power you probably wont see the 30 minutes at half.

Expert:  Wayne Roberts replied 11 months ago.

half brightness*

Expert:  Wayne Roberts replied 11 months ago.

you can go smaller, but the times will decrease accordingly.

Expert:  Wayne Roberts replied 11 months ago.

I hope I have been helpful in this matter, if you have any further questions i am still here. If you have a moment, please rate me so the higher ups know i am doing a good job ;)

Expert:  Wayne Roberts replied 11 months ago.

If there are any other questions you may have i am still here to help,we can go in depth to an exact amount of time you would like your bulb to work, if you take a second to rate my service i would really appreciate it.