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light dimmer

Discussion in 'Technical Discussion' started by gr8trn, Feb 9, 2015.

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  1. gr8trn

    gr8trn Senior Member

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    I would love to be able to dim the light in my salon. They are 12v 10w halogens. Although I know electrons flow through wires I have no practical experience. After thinking I could just buy a dimmer I ralized that 12v light are not likely to be controlled by 120v swithches and dimmers.
    Is this doable? Is there a 12v dimmer or a transformer for a 120v dimmer, am I making any snese whatsoever?
  2. Capt J

    Capt J Senior Member

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    Yes, they make 12 volt dimmers. They are rated in watts, so you have to count all of the wattage of all of the lightbulbs on the string. I also wouldn't get a dimmer rated for exactly the same wattage as the lights, do 20% larger or so.
  3. AMG

    AMG YF Moderator

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    If your boat is running 120 V that is transformed to 12 V between the breaker and the lamp bulb, you should have a 120 V dimmer, otherwise as Capt J says, a 12 V dimmer.
  4. gr8trn

    gr8trn Senior Member

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    Thanks much!
  5. Pascal

    Pascal Senior Member

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    Not sure about that, it really depends on the boat.while this may be true on megayachts, even on boats where you run the genset(s) 24/7 while away from th dock lights are DC powered from the DC system, not converted from 120v

    Yes, you should be able to install DC dimmers.

    Another solution, woudl be to upgrade to LED lights with built in dimmers. Basically you turn them on, they ramp up and you flick them off and on at the level you want,
  6. wdrzal

    wdrzal Senior Member

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    The dimmer should always be rated at or above the breaker size for that circuit (so the dimmer can carry the maximum current the breaker & wire gauge will allow). 10 bulbs @ 10 watts .....100 watts. 3 years down the road it doesn't look bright enough or the store only has 15 watt bulbs. 10 bulbs @15 watts.... 150 watts......dimmer over heats, boat catches fire, you get the idea.
    Last edited: Feb 13, 2015
  7. gr8trn

    gr8trn Senior Member

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    Got it. More reason to love Yachtforums, sage advice.
    Thanks everyone!
  8. Capt Bill11

    Capt Bill11 Senior Member

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    Many times the transformer used is just stepping the voltage down from 120v AC to low voltage AC.
  9. Caltexflanc

    Caltexflanc Senior Member

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    My boat had a slew of 12 volt AC lamps (stepped down from 120) courtesy of a PO. So, yes you need to check.
  10. gr8trn

    gr8trn Senior Member

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    To be complete, we have scrapped the dimmer project, I now moving on to a shower and AC condensent sump box that has a non operating float switch or pump. I only overflowed the box once that I know of so not too bad.