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I was working on my drivers stations yesterday and put the panel mounted fuse holders in place..
However, I don't know what amp fuse to put in them?

I have the PM adjustable power supply.. What size fuse should I pick up?

Thanks!

The lower value fuses that you use the better the protection will be. If the value of the fuses is too low you might blow them when nothing is wrong. It is useful to know how much power your cars actually use. With Slot.it 21.5K motors I have measured close to 2 amp peaks on the track. Slot car motors pull a lot of amps when they are starting up, that drops off a lot once the cars get rolling. I would start off with 2 amp fuses and only go to a higher value if they blow in normal use. For my own track I switched from fuses to resettable breakers. I would stay away from self resetting breakers.

All of our tracks use 3 amp fuses, and that has worked fine for our group for the last 10 years. We run a pretty even mix of mag and no-mag, and three amp fuses seem to cover all bases. If you're going to be running solely no-mag on wood, 2-amp fuses would (probably) be just fine.

Just use a calibrated nail and insert into the fuse holder. That way it will save you lots of money as you wont be needing to replace blow fuses all the time.

Grabs hat and coat and leaves the room quickly. :D


cheers
dr fabio

Per car.

I use 3 amp as well per lane.

Actually, there were a couple of Darwin award participants a few years ago that used 22 caliber bullets in place of the fuses in their pick up truck when returning from hunting. The driver landed in the ER. I here that will really blow your socks off (or maybe something else).

Ventura Alfa

I have been running my routed track for a number of years. Rocky built it for me and posted the build here at HRW.
The fuses I found in the block were 5 amp for each lane. I have been using them without a problem. You can imagine how many fuses I go through. Kids will short out a lane any way possible.
Have fun.
Crab Alley Speedway
Annapolis, MD

The value that I posted was for one car with no traction magnets. The track had a regulated 20 amp power supply set at 10 volts. The power supply had digital amp and volt meters. If you know the resistance of a motor's armature you can calculate the stall current. Even for motors of the Scalextric type that can be higher than you would expect. Once a motor turns over it generates a back EMF and the current draw drops off a lot. The biggest strain on a power supply is when the power first comes on and all of the controllers are punched. If the power supply can't supply enough amps the voltage will sag, even if the power supply is regulated, and the cars's acceleration will be a little sluggish. The period that the voltage will drop is very brief and will not matter much since everyone woud have the same handicap. The exception to that would be a drag strip where you would always want to have full voltage.
On my track fuses only got blown if someome hooked up a controller wrong, that happened often enough that I switched to breakers. If you hunt around you can find breakers for about $5 each. I have seen what can happen if you have no protection at all. I watched a nice custom built HO track burn up because someone hooked up wrong with a car already in his lane. On tracks that had fuses or breakers with too high of a value I have seen even robust controllers like a Parma Turbo burn up. All of the 1/32nd tracks that I race on have XLR connectors, which eliminates the problem of misconnected controllers. I would like to have them on my HO track, but I do not think that anyone would put XLR connectors on their controllers.