Convert DC Marine Lights to AC (to attach to house)

[randy]

I want to make these lights run on AC. I could have simply used an off-the-shelf AC-DC converter, but my house (new construction) contractor already ran residential AC wires from the house panel, to on/off switches, and to the outside of the house. The house is almost finished and the inside and outside walls are closed in and finished so I can't make a new run of wires. So, I either figure out how to convert AC to DC with a very small device that can go behind the lights (maybe in the wall from the outside), or figure out how to modify the lights themselves to run on AC.

Could it be as simple as finding the right AC bulb to fit this housing? Or modify the internal parts of the housing somehow to accept a bulb that will run on AC?

Thanks for any ideas.

Randy

 

[MikeMl]

You will have a hard time finding a 120VAC lamp that fits the fixture without changing out the socket. I would use a 120V to 12V weatherproof transformer such as is used for Malibu lights, mounted outside. That way, you can use the lamps and fixtures unmodified.

 

[marcbarker]

If I were you I'd I'd bite the bullet replace them with 120 V lamps. Pretty lights, shame.

Even if you did modify it, years later if something went wrong, they'd probably get wired directly to the line current by a do-gooder or well-meaning electrician who doesn't know any different.

 

[Hero999]

What voltage do they run on?

But a transformer with the correct voltage, doesn't matter if the output is AC or DC, it just needs to be the right voltage. Label the wiring to indicate that it's a lower voltage to prevent some future electrician connecting it directly to the mains.

 

[randy]

Interesting thoughts. I'm almost inclined to figure out how to tackle changing out the sockets to hold an appropriate bulb, or, push the cables back into the gargage and surface mount converters there. Then, bring the wires back to the same location. I do so love the lights. The photo below shows the intended locations of the lights.

 

[marcbarker]

About the definition of 'AC' and 'DC'. To most non-electrical people, AC means 'line voltage 110/230' and DC means 'batteries' and car/boats. The problem is that the 'buried in wall' wiring is standard line current wiring and coloUrs, and that replacing the wiring with 'LV wiring' is presumably out the question.

What voltage do they run on?

But a transformer with the correct voltage, doesn't matter if the output is AC or DC, it just needs to be the right voltage. Label the wiring to indicate that it's a lower voltage to prevent some future electrician connecting it directly to the mains.

They look like 12 V 'festoon bulbs' 5 watt. As pointed out above, they'll work fine off 12 V AC too.

 

[DSGarcia]

Randy,
The bulb looks like a standard 12V automotive dome light. I would get a small 12V doorbell transformer (as long as it provided enough current for the three bulbs) and fit it into the outdoor electrical box if there is room (another option is to replace it with a deeper or larger "remodel" box if you need more room). Put an outdoor cover on the box. You may need to drill a hold and seal it around your low voltage supply line exiting the box depending on how you run the line to your light fixtures. You can run low voltage wiring to your three fixtures; wire them in parallel. Because it is a low voltage system, the "light fixtures" do not need their own boxes but you can mount them directly on the wall and the wire can be run on or in the wall (but use a cable that has a UV resistant jacket if the wire is outside).

Check your voltage under load to see what your transformer is providing in a loaded circuit. You can buy some bulbs at the local auto supply store for testing or replacements.

Please post a picture here when you have it all done.

Thanks,
Dale

 

[marcbarker]

Randy,
I would get a small 12V doorbell transformer (as long as it provided enough current for the three bulbs)

Even easier, there are standard 12 V transformers available for LV lighting. Even if you bought a LV lighting kit and threw away the lamps that came with it, you have a small transformer which is continuosly rated and clearly spec'd for the wattage of the lamps.

 

[randy]

Don't know if this helps any, on one end of the bulb it says:
OSRAM 12V 10W *-n4R-

 

[Ghosty_Ghoul]

Then you'll need at least a 30VA transformer assuming you've got three lights.