karn@eagle.UUCP (Phil Karn) (10/21/83)
You can make your own surge limiter, if you are so inclined, with a resistor and an AC relay. Put the resistor (size varies with power requirements, but typically 10-20 ohms at least 10 watts) in series with the ac power to the load. Wire the relay coil across the load and the contacts such that when the relay pulls in, the resistor is shorted. The resistor limits the current to the load until the power supply capacitors have charged. At this point, the voltage drop across the series resistor decreases, allowing the relay coil to pull in, shorting the resistor. The result, if you have it right, is a short "zzzzzing!" sound from the relay when you turn on the power, which should of course be done on the line side of the surge circuit. I've put this circuit in many high power capacitive-input power supplies and it has worked fine. No more blinking lights, fried rectifiers and tripped circuit breakers. Phil Karn