[alfamuppet]

Hi


Your using a design of dc controller built for the 1970´s fork lift truck market. My background is military electronics and I believe you are becoming un stuck with age related problems. No semiconductor device has a life beyond 20 years, at which point it will fail or semi fail intermittently. Electrolytic capacitors have no life after approximately ten years, even less if they are unused (about 3 years) the ESR of them will rise to practically not represent a capacitor at all, the rest of the components i.e. resistors, polyester capacitors etc will deteriorate voltage wise and will either breakdown or short circuit. Cut a lot of heartache out and expense, purchase a modern dc controller, check your motor winding´s with a Megger (insulation tester) and replace if necessary. I know it is not the advice you were looking for but is the most practical and economical and the only certain way your Uncle will be able to drive his EV.

 

[alfamuppet]

I have GE EV-1 controller from 1969. Works fine.

I don't think it even has electrolytic capacitors.

Semiconductors only being rated for 20 years.... come on man. 20 years ago was 1998. Yeah a few devices are going to go bad over time, but, it's not a plague (except for the capacitor plague, devices from early 2000s infamously fail due to attempted trade secret theft and counterfeit electrolyte failing).

It would certainly be easier to spend $100 on a little golf kart controller and be done with it, but, he's not condemned to failure just because he's using an old controller.

After 20 years every semiconductor device becomes a lottery, the percentage of failures starts to climb slowly and increasingly, it's the chemical breakdown of the metalised layers used in production of integrated circuits/diodes/thyristors(EV1) etc. Your driving an ev on the road and I would not want anyone to have a random failure whilst driving which could be avoided just by having a new dc controller. Granted the EV1 is a bit stylish - but leave it for the mantelpiece not the highway.