Testing meters

[Robdean]

OK, my skills are limited as far as testing electrical meters so I thought one of you clever people may be able to help me here. I want to be able to test both the ammeters and voltmeters which are in use at the moment for Year 8 and shortly for Year 9. I suspect some meters have been burnt out. I have 7 labs here in 3 different buildings and the meters are all over the place.

Can someone please give me some really simple instructions as to how I can easily test the meters - I do have a multimeter at my disposal.

Thanks heaps, Robdean

[Slartibartfast]

Use a power pack and 2 leads for the voltmeters and for the amps, use 3 leads with a lamp on stand in 1 circuit as in the picture below. You are only seeing if they work or not aren't you, so this will get you by just fine.

For actual level of problem and diagnosis use a multimeter. For amp meters switch the multimeter to the 'omega' symbol and place each probe (1 red 1 black) in the terminals of the meter you want to test. If the needle on the multimeter jumps to a reading the circuitry is fine.

Remove the 4 screws and open the backs and it's usually visable why they don't work. Students usually run too many volts through them and it burns out a wire or melts 1 end. Easy to resolder a new bit in or reuse the old length if enough remains of it.

This photo shows that using a globe, it proves the circuit exists and the amp meter is registering the load/draw the globe and wires are providing. The metre is working fine.

[Robdean]

Thanks Richard - I'll be on to it - in my "spare time" of course ha ha. I look after 7 labs here, 3 different buildings, 2 different levels and shortly will lose time in Science and have to divide my time with Home Ec! Should be an interesting juggling act!

[Slartibartfast]

Good luck! I get stuck into my repairs on sports days.