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Digital multimeter went crazy

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Hello,

I've got a Discover (I suspect that's just a generic brand) digital multimeter, which I recently used to measure the voltage on an electric malfunction on my kitchen.
Immediately afterwards I noticed that the multimeter voltage reading went crazy. Even if the two terminals are shorted, the reading randomly jumps from minus infinity (indicating that it's outside of the specified range) to infinity and various in-between values. This happens whether the multimeter is set to measure DC voltage, AC voltage, or even current.
I had thought that the ohmmeter was working, but it isn't - it consistently measures infinite resistance even if the terminals are shorted.

What might be wrong with my multimeter? Is there any hope, or should I just throw it away and buy a new one?

Thank you for your help.
 
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Yes I did, it was set on 600V which is the maximum scale on my multimeter. Also, the circuit board does not have any unusual smell as far as I can tell. It doesn't even look burnt - but I'm by no means an expert, so don't quote me on that.
 
Have you tried it on a known value, for example a charged battery or similar, no load readings on some of the cheaper meters can be erratic at best, generaly speaking with cost of replacing the meter, if it is faulty, it is hardly worth a repair, unfortunatly we live in a throwaway society.
 
Just tried it on a 1.5V battery. The reading is still erratic. It used to work fine even with zero load.
I guess I'll have to replace it after all...
 
Have you checked the internal fuse. If you had at set for Resistance some time with power applied to a circuit... poof. Then the meter goes erratic.
 
just rig up a quick continuity tester with a battery and bulb just for testing the fuses etc.
 
short the fuse and see if it works measuring a battery.
 
I don't think anyone has mentioned to check or replace the batteries and before you do clean the battery contacts.
In most cases if the simple fixes don't solve the problem ,then it's time to replace it.
 
Have you considered the function switch could be shorted? Your chosen function could be measuring an adjacent function, or multiple functions if the switch contacts have been fused together by an electrical short.
 
Might not be related to you problem,but I had trouble with high resistance in the probe leads,this was caused by continuous reading of very high ampages.and rendered the leads useless for measuring ohms.my fault,guilty, Good luck Terry
 
I watched a profesional electrician "nuke" a brand new $300 Fluke meter while trouble shooting the torch on a plasma cutter! :D
Most good plasma cutters use high voltage pulses to start the arc. Then switch to cutting current mode once the arc has transfered.

I told him not to do it too. He said, what do YOU know about plasma cutters?
(Rather angerly too!) Then pressed the button. :mad:
5 kv jumped the internal circuits then it transfered to 50 amps cutting current!
The meter glowed brightly, then smoke and flames shot out the seams! :eek:

I just laughed and walked away! Laughed hard too! Real hard! :D :D :D :D
 
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Wish I was there for that tcmtech. But about 20 feet away =)
 
My self employment does not always pay as well as a typical year round job but days like that make it soooo worth it! :):D:)
 
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