Originally Posted by
Ah Me Ting
100% recommend you do the googling and get some specs of the power draw. You really can't do it by trial an error.
How many switches (circuits) are you running?
What is the amp rating of the wire you used?
What will the total load be, in amps, on each 'circuit' if all devices on that circuit are switched on?
As a very tough guide, LED Nav lights, cabin lights draw bugger all, so say 0.5amp.
Headlights or spotlights can vary from not much to oh geez really that much.
Bilge pump, deck wash pump, live bait tank pump, etc will draw more than you think.
VHF, Sounder, GPS will draw less than you think.
The trick then is if you have limited switches and circuits you need to balance them by calculating the draw from the devices on each circuit.
Trial and error will not work as, hopefully your wire rating is way above the total power draw of any one device. So, getting a fuse to blow means you need a device to fail.