to find out how much current is being drawn, connect an ammeter in series in the line, unless you have a clamp around meter that reads 0-5 amps. the numbers on a glass cartridge fuse indicate the type of fuse, type of insulation used and the amps. the other numbers could indicate time delay etc. SAE fuses are almost always automotive and are rated 12 volts. other glass fuses have the voltage stamped on them. 125V, 250V etc. rarely will you see anything higher than 250V. a fuse listed as 2a @ 250v will safely pass 2 amps operating at 250 volts or lower. now if you reduce the voltage to 120 volts that 2amp fuse will now safely pass 4 amps. an decrease by two of the voltage will increase the amp draw by 2 amps.
this site will give you several glass fuse choices:
http://www.bb-elec.com/product_multi...ltiFamilyId=30