Multimeter question

[amadeok]

Hello,
I have a 6000 count multimeter i was using it and i blew the 600mA fuse, so i couldn't measure the current with the red probe on the VOmA socket, but then i tried also the 10A socket and still i got 0 always. So i opened it, replaced the 600mA which was completely blown, i took out the 10A fuse and tested it and it gave 0.4 ohm resistance, and it also looked visually in good condition. So i put back the 10A fuse inside and tested it again and now everything is working properly. I don't understand, why is it that the the 10A socket wasn't working properly?

 

[dr pepper]

Maybe the 10 a range uses the 600ma range's input shunt and fuse.
I had a meter that lost various ranges when I blew a fuse, such as capcitance and frequency, it depends on what part of the circuit the fuse is in, if it was in the ground line maybe that would explain it.

 

[Grossel]

Haven't read the schematic, but maybe inputs are linked - e.g. current/voltage divider.

 

[amadeok]

This is a picture before changing the blown fuse:

 

[amadeok]

I'm never supposed to try to measure voltage when the meter is set to an amperage setting right? I think that's how i blew the fuse.

 

[Nigel Goodwin]

I'm never supposed to try to measure voltage when the meter is set to an amperage setting right? I think that's how i blew the fuse.

Yes, it's essential that you use the correct setting.

 

[dr pepper]

Yep as nige says.
Also dont try to measure voltage with the leads plugged into common and 10a sockets.

 

[amadeok]

Yes, it's essential that you use the correct setting.

And this is true for both the 10A and VOmA sockets right?
I've also read that before measuring current the circuit must be powered off, then connect the meter in series and then power it up?

 

[Nigel Goodwin]

And this is true for both the 10A and VOmA sockets right?

Yes, for any current range.

I've also read that before measuring current the circuit must be powered off, then connect the meter in series and then power it up?

No, no particular need to do that - although I suppose it really depends on exactly what you're measuring.

 

[dr pepper]

On 10a range powering down might be a good idea, same goes for voltages over 50v, then your not going to create big sparks or zapping yourself.

 

[Reloadron]

Good image as you can see the 10 Amp current path up from the 10 Amp connector, through the fuse, back down and through a 5 milli Ohm sense resistor to the Common input. It's nice to see a decent image with good detail.

Ron

 

[be80be]

And this is true for both the 10A and VOmA sockets right?
I've also read that before measuring current the circuit must be powered off, then connect the meter in series and then power it up?

If you like the meter leads it's better to hook up when using it in 10 amp range it's easy to burn the tips from arcing.

 

[Nigel Goodwin]

Good image as you can see the 10 Amp current path up from the 10 Amp connector, through the fuse, back down and through a 5 milli Ohm sense resistor to the Common input. It's nice to see a decent image with good detail.

Ron

Must admit, I was also well impressed with his picture