Yesterday i wanted to measure ma on my aaa battery and i turned on the multimeter, set the red test lead to 400ma fuse(microamp and miliamp mode) and tested it on microamp mode, reading said ol(overload), i panicked and switched it to miliamp mode and it showed 355ma.Is my fuse blown? Do the multimeter use the other fuse if the 400ma fuse is blown? I did the continuity mode and the larger fuse beeps but the 400ma fuse does not beep(open circuit).Amperage reading is working although when reading a alkaline battery amperage is constally dropping but that is normal behaviour right?
And what would happen if you use more than 350 ma on microamps mode?
Thanks
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Do you know that when measuring current a multi-meter has to be placed in series with a load and not in parallel like when measuring voltage?
If you just discharged a battery into your meter, that is you shorted out your battery you will blow the fuse.
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Hello diexd
Take a view here to gain the knowledges:
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You're not the first one that made that mistake.
Blowing the current fuse of a DMM is quite common.
Just replace the fuse, and keep a second new one handy.
Leo..
On one hand it would be good to have a DMM with resettable fuse, on the other hand - then you would never learn.
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Problem is that they are too slow to blow to protect any of the electronics inside the meter.
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Okay paul, thanks
@Grumpy_Mike @Wawa is the fuse blown then?? I can still measure amps tho
Yeah, i heard that
Do you mean at the normal 10A range? Yes there is normally another fuse for that.
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No i mean, when i put the 400ma mode amps still measure
On 10a mode amps works too
If you want to test a battery and be 100% safe for you DMM, use a shunt with low resistance in series with the battery, and measure the voltage drop over the shunt.
Then you calculate V/R(esistance of the shunt) to get I.
Edit: Note that this will drain a battery fast if you leave the shunt connected for a long time, you just wanna connect and do the voltage reading, that's it.
Thanks ledsyn
OK.
That must hang off your 10A fuse then, after all 400mA is nearly half an Amp so it makes sense.
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So when lead is inserted on 400ma fuse mode and i want to measuge ua,ma and a if the 400ma fuse is blown the multimeter goes to 10a mode automaticly?
No. It is telling you that the 400mA range is hooked up to the 10A fuse anyway. It is ranges more sensitive than 400mA that are passed through the 400mA fuse.
A Fluke?
Kps
Found it!