AC lamp holder on 12v DC system

[loggio]

Hi guys,

I'm in the process of making a portable solar power station for when I'm camping, nothing big... just need it to run a 12v computer fan and charge a few phones and run a light or two at night. I have a 35W solar panel and an 18ah battery connected to a small 10amp solar controller module.

I want to hang a light globe in my tent and run a low wattage CFL or LED globe from it.

My question is, can I use a standard every day lamp holder socket from a 240v desk lamp like this:


cut the cable, add a 12v accessory plug to the end and then connect a 12V DC LED or CFL globe to it?
or do i need a special lamp holder for a DC system??

may sound silly, but I've never actually wired one if these before and am not sure if they are anything more than a just socket.
I couldn't imagine it would matter if the circuit was either AC or DC as long as the globe is the correct type, right?

thanks in advance guys!

cheers,
Loggio

 

[Haf-E]

It works fine- the real limit is the current (amps) which will be fine as long as the 12vdc lamp is low wattage. If its rated for 60 watts at 240vac that would be a 0.25 amps- so that equals 3 watts at 12vdc. Its probably rated higher than 60 watts too.

I've had the built in switches on the cord/ lamp holder fail over time... they end up becoming a poor connection if used much. I would go with led lamps- usually much more durable than fragile cfl's.

 

[Wildcat]

yes it will work. i made a 12v led light out of a cfl base. i used an 1157 led, replacement socket from advanced auto, pvc, cfl base. the wire nuts were temporary during testing. completed light has shrink tube.

 

[4x4junkie]

^^
Good to see others building & modifying existing stuff to make it work for their needs.

Agreed, I see no issue at all putting a lower voltage through a socket than what it's rated for. I would even say it's safe to exceed it's current rating by some 50-100% @ 12V since there isn't the large amount of heat associated with a bulb (globe) drawing the same current at 120 or 240V to go with it (you'll occasionally find switches, sockets, etc. with higher current ratings at 120V than at 240V for these reasons).

 

[evldave]

This should work reasonable well...Just for the sake of making you aware, though...DC current through those switches will eventually corrode the contacts and you could get a short. Not likely to be a significant issue since you aren't running them at their (usually) 660W max rating, but it's something to think about - DC switches are tested with DC, lampholder switches aren't and I know they'll fail eventually.

That said, your entire setup will likely outlast your desire to use it But I've seen lampholders fail and catch fire (again, with greater currents, but still) it can be a rather fun display of sparks, fire, and melting plastic

ps-would do this, and have, so we aren't exactly talking about a 90% chance of failure or anything