XFR is 120V primary, 12V secondary.(Basic Kichler 900W landscape XFR). Customer#1= out of 80 bulbs, 40 were burnt out, definitely blackened, some did have water in sockets.
Bulb life goes down by the square of over voltage. 12.5 V supplied vs. 12 V designed. 4% over voltage squared equals 16% shorter life.
Measure the voltage at the transformer output terminals, the voltage at the closest lamp socket, and the voltage at the farthest lamp. I would expect that the transformer is probably putting out about 14 V. If this is the case, as the closest bulbs burn out, the voltage rises for the rest of the bulbs, and they burn out going down the line.
900 W / 12 V = 75 Amps
Check if there is a voltage adjustment tap to reduce the output voltage.
