12v conversion

Joe3253 · Sep 28, 2020

I've just converted my 1953 NAA tractor from 6v to 12. I don't want to replace all the 6v lights unless I have to.
Is there an economical way to just put a resister into the light switch circuit to make the 6v lights work instead of replacing all the lights? I have about 100w of lights, so if this is possible, please let me know what I would need and where to buy it. I am almost illiterate about electronics so any info would be appreciated.

Steve@Advance · Sep 28, 2020

Not really a practical way to do it.

It would take a resistor at each lamp, or sized for each circuit, but if one lamp failed it would send too much to the remaining lamps.

What you could do is rewire the head lamps of the same wattage in series. Say you have 2 6v head lamps, rewire them in series to 12v. This will only work with lamps that are not grounded through the base of the socket.

Goose · Sep 28, 2020

My instincts tell me resistors would cost more than light bulbs.

Surf online. You can get some real deals on both 6v and 12v bulbs.

David G · Sep 28, 2020

No practical way to do it.

RCP · Sep 28, 2020

I suggest you replace the bulbs and while you are doing it change to LED bulbs.

David G · Sep 28, 2020

Agreed

Hayfarmer · Sep 28, 2020

to me that was one advantage of conversion, much easier to find 12 volt bulbs than 6 v

Pete in Holland MI · Sep 28, 2020

Sealed beams for my Jubilee when I converted it were about $9 each if I recall. Do it right the first time.

55 50 Ron · Sep 28, 2020

QUOTE "but if one lamp failed it would send too much to the remaining lamps."

Too much? They are all parallel circuits from the 12 volt source to chassis. If a parallel path opens the voltage on all the rest remains about the same (assuming it's a good strong battery) so where does the "Too much" come from going to the remaining lamps? (Maybe I didn't read the original post correctly?)

banjoman09 · Sep 28, 2020

Simplest is to replace the bulbs - my opinion.

JMOR · Sep 28, 2020

(quoted from post at 22:31:59 09/28/20) QUOTE "but if one lamp failed it would send too much to the remaining lamps."

Too much? They are all parallel circuits from the 12 volt source to chassis. If a parallel path opens the voltage on all the rest remains about the same (assuming it's a good strong battery) so where does the "Too much" come from going to the remaining lamps? (Maybe I didn't read the original post correctly?)

ep, either didn't read or read wrong.....try again in morning.

Steve@Advance · Sep 29, 2020

Ron, the resistor has to be sized to the load to get the correct voltage to the load.

If part of the load is removed, then the voltage goes up to the remaining load.

Think of it as water flow. You have a pipe with a tee, water flowing equally through each side of the tee. Block one side, the pressure and flow to the remaining open side will double.

Determined · Sep 29, 2020

Like Steve said, you could rewire say 2 front lights together in series and 2 back lights together in series and it will work.

Problem is with them in series when one bulb burns out they both quit, not something you want when driving in the dark.

But being that you said economically I am guessing the cost of the wire and your time will exceed the cost of a few bulbs.

55 50 Ron · Sep 29, 2020

I totally understand what you say, but I disagree UNLESS there is a series resistor ahead of the point where the parallel circuits begin. I don't think there is a series resistor like that mentioned in the original post - at least I didn't get that impression.

I sent you an email too.

Ron

12v conversion

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