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BOBS66440's avatar
BOBS66440
Explorer
Dec 30, 2016

Dumb Lighting Question

I want to replace a ceiling light fixture (mini fluorescent) in my RV that's not working with a new one (can be led or whatever). I'm not too keen on electrical theory and am wondering what type of fixture I should get that will work with 12v and 110v. I see lots available for 12v but I'm not sure if they will work on 110V also. Thanks!
  • It's probably only 12 volt. Never heard of a 12/120 volt light.
    All lights in my unit are 12 volt.
  • Most RV lights are 12v only. I've seen a few older RVs with 120v lights. I've never seen a dual voltage light.
  • There are no dual voltage fluorescent bulbs available; in fact, there won't be too many fluorescent bulbs around, period. They're now banned from US production &/or import, as of 1/1/17.

    Go to LEDs now, and save yourself the trouble of conversion later.
  • Lights are 12V and work equally well with 120V which uses the charger to keep the battery charged and lights working.
  • Mandalay Parr wrote:
    It's probably only 12 volt. Never heard of a 12/120 volt light.
    All lights in my unit are 12 volt.
    I guess this is where my confusion comes in. I have the house battery and start battery disconnected but have the shore line hooked up to an outlet in my garage (110v) and all the lights in the RV work. I assume there must be a voltage limiter somewhere to drop it down to 12v?
  • My converter converts 110 down to 12v so my 12v stuff still works while plugged into shore power and my battery is disconnected. I do have one light that is strictly 110 and it will not work while dry camping with only the battery powering things.
  • BOBS66440 wrote:
    Mandalay Parr wrote:
    It's probably only 12 volt. Never heard of a 12/120 volt light.
    All lights in my unit are 12 volt.
    I guess this is where my confusion comes in. I have the house battery and start battery disconnected but have the shore line hooked up to an outlet in my garage (110v) and all the lights in the RV work. I assume there must be a voltage limiter somewhere to drop it down to 12v?


    More or less. There's a device called a converter that is a 12V power supply; it serves to charge the house battery and to power 12V systems when connected to 120V power. It's not really a voltage limiter per se, which would be very inefficient and produce AC rather than DC output, but the concept is what you're thinking of.

    In general, if you're plugged into 120V power, there's no good reason to disconnect the house battery. Many converters aren't designed to work (or at least work well) when there is no battery hooked up. It would be a good idea to periodically check the water level in the battery and top off as needed, assuming it's a flooded battery. (Some, mostly newer, converters will operate properly and produce clean 12V power without a battery connected.)