WW2 Anti-Aircraft Gun Motor Guidance required.

Thread Starter


Joined May 21, 2021
Hi all,

I'm looking for some guidance for the modification of an old WW2 generator to provide 12v (20amps max) to charge some batteries on a WW2 Anti Aircraft Mount.

Generator pe77.png

The Problem:

  1. The generator currently produces 110v 250watt at around 2 amps and was used to run electrical devices in the field.
  2. I want the generator to produce 12-15v up to 20amps max to charge 12v batteries when the gun mount is being used.

The Goal:

  1. The aim is to recreate the original wiring diagram below with some altercations to allow for a 12v-15v charge for the batteries.

Power Charger Diagram.png

My Proposal:

  1. This is mapped out below in the wiring diagram. Hopefully clear enough to understand the basic gist of what I'm trying to create.

Asset 2@300x.png

It would be great if anyone who is a bit more electronically savvy than me can let me know if they will think it will work or if there are any red flags or improvements that need to be made for this to work.

I really appreciate any input and any questions just ask.

Many thanks in advance!

Plug a 120V battery charger into the generator set.

Or construct one using a transformer-rectifier arrangement utilizing an auto-reset circuit breaker and voltage monitoring circuit for overcurrent and overvoltage protection. Dead simple battery charger.

No sense re-inventing the wheel.

Thread Starter


Joined May 21, 2021
I like your thinking.

I've had a look at off-the-shelf battery chargers and many are AC input. The generator has a DC supply (I forgot to mention). Would it be worth inverting or just creating it from scratch?

It seems constructing one may be a better option. My worry is my beginner level of electrics and handling the high voltages maybe a little risky. Unless it is as straightforward as you make out!?
If it's a DC generator then that changes everything. A DC buck converter suddenly makes a lot more sense now.

You could probably find a solar charge controller with a suitable voltage range that will do the job, provided it has a current limiting feature.