Voltage of artillery tow light

[philipgslattery]

Hi All,
I am currently in the process of assembling the components to make a correct tow light for the 37mm atg.

The questions are: what is is the correct voltage for the lights and does it matter?

Sometimes the atg will be towed behind a 6 volt jeep and sometimes behind a 12 volt scout car.

If I install a 6 volt globe will it blow when towed behind the scout car, or if a 12volt globe is used will it illuminate when towed behind the jeep?

There might be some obvious answer, but I have been scratching my head over this for a while.

Thanks

Philip

[Joe Gopan]

The Bulb Voltage must match the Tow Vehicle. Things were a bit primitive during WWII.

[philipgslattery]

Ben ( I assume that is your proper name), Thanks for the reply.

I have never tried it but do you know what might happen if a 12 volt globe is hooked up to a 6 volt system and vice verse?

Also do you know if something untoward should happen, is there some way of preventing this besides changing the globes?

Do you know what the army did in practice because I have seen photos of the 37mm atg being towed behind both jeeps and scout cars?

It would have been fiddly to change globes.

Thanks
Philip

[artificer]

I am currently in the process of assembling the components to make a correct tow light for the 37mm atg.
The questions are: what is is the correct voltage for the lights and does it matter?
Correct voltage is the same as the tow vehicle's. Yes it does matter due to the following
Sometimes the atg will be towed behind a 6 volt jeep and sometimes behind a 12 volt scout car.
If I install a 6 volt globe will it blow when towed behind the scout car?
If the scout car is 12V, yes it will shine brightly for a very short while, as it burns out nearly immediately.,
If a 12volt globe is used will it illuminate when towed behind the jeep.
It will most likely illuminate, but not too bright on 6V. Try your 12V test light on a 6V battery to get some idea

I would suggest the units with these weapons would have had either 6V &/or 12V cables ready to clamp to the gun in question depending on vehicle towing, that is if they bothered with hooking up the gun's light.
Plus there were plenty of cables laying around with burned out bulbs.

[Gordon_M]

On all the small interchangeable towed trailers, they were 6 volt units.

If the towing vehicle was 12 volt, it had a resistor box at the rear of the chassis to drop the trailer socket voltage to 6 volts.

[philipgslattery]

John and Gordon,
Thankyou for the thoughtful replies.
What you have said makes a lot of sense.

I guess for me in practice I will have to change the bulbs when towing behind the different vehicles(unless someone can give me more info. about the resistor box).

Thanks

Philip

[Gordon_M]

There is a Dodge part number somewhere for the box used on the Command and Carryall, but don't have the number to hand

[Gordon_M]

Scroll down to page 36, bottom centre, Trailer Resistor Box

http://www.vintagepowerwagons.com/pdf/p ... trical.pdf

NOS Trailer Resistor Box
Reduces voltage on 12V vehicles to pull 6V WW2 trailers.
Vehicle Type: B,C Part #CC1089661 $38

[tankbarrell]

Gordon is correct, all trailers were 6 volt. Scout cars did not have a trailer lights socket so it would not have been an issue at the time.

[philipgslattery]

Gordon,
Thankyou very much for the info. and contact details.
Thanks to you I have just placed my order for the Trailer Resistor Box.
It seems logical that the army would have come up with something such as this.

Tankbarrel, thankyou also for the input.

This is such a great site.

Philip

[Gordon_M]

That's what we are here for Phillip, you are welcome.

That box is a late Chrysler part number, but I expect it would have appeared on numerous vehicles. I do recall seeing it mentioned as part of a kit to field-fit trailer socket and wiring - maybe on a Carryall or very early Command where it wasn't standard.

The wiring diagram will be in the Dodge T214 manual somewhere,although I don't expect it will be a complex fit.

[artificer]

I would suggest the units with these weapons would have had either 6V &/or 12V cables ready to clamp to the gun in question depending on vehicle towing, that is if they bothered with hooking up the gun's light. Plus there were plenty of cables laying around with burned out bulbs.

This was an incorrect suggestion/assumption on my part & I've learned something new, that I was unaware of.
The other tech information offered was correct.

On all the small interchangeable towed trailers, they were 6 volt units. If the towing vehicle was 12 volt, it had a resistor box at the rear of the chassis to drop the trailer socket voltage to 6 volts.

Thanks Gordon: The Northern hemisphere shift corrected my earlier post's suggestion & I'm glad you guys helped Phil who now has the correct answer & a resistor unit on the way.