Depends on what fuse, and where in the chain. There are a couple of std barrel fuses, but the ones that usually blow are soldered on the boards. You'll have to use a multimeter and test to see which one. It's been a hot minute since I dealt with Roland's, maybe someone else can point out the most probable one/ ones to check. I've had to replace them in the past, they're pretty readily available on line, inexpensive, and look like the ones in the pic.
Always replace with the same value, these are what protect the boards from frying.
For any printer, if you're going to do any repairs where you even have to even touch wires, always fully disconnect power, and let it sit for a while for capacitors to discharge. Something as simple as inadvertently disrupting a ribbon cable by moving it out of the way to get to a screw or something else can cause a short, they're extremely sensitive. Always double/ triple check that ribbon cables are seated firmly and correctly before powering up again after doing any repairs. Ink is conductive too, so always make sure everything is clean before assembly and powering up.