Test of my multimeter any suggestions?

I have a 400Ma selection for current fused and I blew it and replaced it, but instead of it blowing at 500ma it took 900ma constant wallwart power? I need to test it to see if its accurate is there any setup anyone can help me with involving NiMh batterys and resistors that will give a universal reading below 400Ma? Or any other sugestions?

Connect a 3 to 5 ohm resistor (1/2 watt or more) accross a NimH cell and measure the voltage across the resistor. Use Ohm's Law to calculate current; Volts/Ohms = Amps.
Voltage measurement example: Connect cell+ to voltmeter+ and resistor, connect cell- to meter- and other end of resistor.
Then put your ammeter in series with the resistor to see if the current shown is the same as calculated.
Current measurement example: Connect cell+ to resistor, other end of resistor to ammeter+, meter- to cell-.

This isn't perfect, but should be good enough to see if the ammeter is still in the ballpark.

sounds like you need a 'fast blow' fuse.. not very likely that the 900mA 'constant' would affect the meter though.. in amps mode.. the meter really is just a shunt for the current.. and a small amount of voltage is tapped off to measure.. the fuse is mostly to prevent generating too much heat on the shunt resistor.

crux's ideas are pretty sound to get a ballpark answer to your question.. the best way is to use a comparison meter, or use a luxeon driver with a constant-current you know the setting on (or can calculate from a resistance ala VIP or fatman driver).. they are deadly accurate.

-awr

Well I tried Crux's idead and the 10 amp range worked , yet the 400 ma was registering 133 ma! I even bypased the fuse with wire and got the same reading. So basically according to Ohms law the 10 Amp range was correct and the 400 Ma wa off so I'm looking for an exchange. Thanks for your help and knowlege in this matter!!!