I am using the Keil MCB2300 board. I am powering it from a 5VDC supply. I would like to fuse this power connection so that I don't over amp the board. Can someone recommend if this is possible. I see that the board should draw ~120 mA. I've never heard of a fuse that low (5VDC and 120 mA).
A fuse sees current - not voltage. The voltage figure is just a safety value. So you would probably have to look for a fuse with a rating of maybe 125V or 250V.