I’ve come across a couple AC 70W computer power adapters that put out 24 volts and 3.5A’s. I’m thinking of using them to power accessories on my layout: lights in buildings, coal tower, crane, etc…. My concern is that the voltage is too high and may end up frying everything. Any suggestions or thoughts?
As long as you use 24-volt lamps, there should be no problem with the lights in the buildings. You can also use a suitable dropping resistor in series for an accessory that is a constant load when on, like a crossing gate or semaphore; but you’ll be wasting about half the power in the resistor.
Seventy watts at 24 volts is slightly less than 3 amperes.