jelliott
Member
I've automated the very crude charger in my brother's 35-yr-old electric car, with relays that switch the 120 VAC input from one transformer tap to another, and ultimately pull power from the transformer entirely when the batteries are fully charged. Not surprisingly, this can produce substantial transients that I'm concerned may eventually damage the transformer. (The relays have already had to be replaced, despite being rated for higher currents than they’re actually carrying.) I’m looking for advice on the best way to suppress these transients. I had a SiBOD device that I found on eBay between each transformer input tap and the 120 VAC power source, which seemed to help (i.e. the car became less likely to trip the household circuit breaker when switching rates or shutting off). But then one of them shorted out such that it provided a path for power to continue flowing to the transformer after the relays had pulled power to shut it off. And since replacing that damaged one, the car has tripped the household breaker at least once when it tried to shut off, so this solution is clearly imperfect. I’m vaguely familiar with the concept of RC snubbers, but wouldn’t know how to properly spec one even if I did have complete specs on this transformer (which I don’t).
Thanks in advance.
Thanks in advance.