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DMM Lead Arc getting voltage from power strip

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helius:
The "wire with a little bead on it" is a K-type thermocouple wire. It is designed for high-temperature use and isn't going to just melt (although the heatshrink could).

Multimeter fuses are for protecting the current shunt, they do not do anything to the volt measurements and those still work after the fuse blows.
If your meter only reads AC amps using the clamp, it is unlikely to have any fuse.

DW1961:

--- Quote from: helius on July 25, 2020, 10:24:17 pm ---The "wire with a little bead on it" is a K-type thermocouple wire. It is designed for high-temperature use and isn't going to just melt (although the heatshrink could).

Multimeter fuses are for protecting the current shunt, they do not do anything to the volt measurements and those still work after the fuse blows.
If your meter only reads AC amps using the clamp, it is unlikely to have any fuse.

--- End quote ---

Great information. I appreciate you taking the time to share that information. It's very interesting to me.  I see because the Clamp Meter is not a part of the circuit, so there is no danger of shorting it. Again, thanks a lot for that information. Read up a little on the K Thermo material, etc. Much thanks again.


Is there anyway I can modify it to work as a temp probe for my soldering iron?

TheMG:

--- Quote from: DW1961 on July 25, 2020, 08:10:23 pm ---I was checking voltage at a power strip and had an arc that partially melted the tip of my lead (It put a little melt point on it). I may have inadvertently had it on DC voltage. Would that cause an arc, or just an out of range signal on the LED? It's a good way to ruin leads, so I don't want to repeat that if possible.

--- End quote ---

That multimeter does not have any current measuring function on the banana jacks. Thus, you should NEVER under any circumstance get any kind of arc from the leads, no matter which function you have selected! Any half decent DMM should be able to handle its full voltage rating on any voltage range, AC or DC, ohms, continuity, diode check, and any other mode it has, without any damage to the DMM itself or the leads.

Basically this means your DMM is a piece of junk. It's either defective or poorly designed. You get what you pay for.

DW1961:

--- Quote from: TheMG on July 26, 2020, 01:07:41 am ---
--- Quote from: DW1961 on July 25, 2020, 08:10:23 pm ---I was checking voltage at a power strip and had an arc that partially melted the tip of my lead (It put a little melt point on it). I may have inadvertently had it on DC voltage. Would that cause an arc, or just an out of range signal on the LED? It's a good way to ruin leads, so I don't want to repeat that if possible.

--- End quote ---

That multimeter does not have any current measuring function on the banana jacks. Thus, you should NEVER under any circumstance get any kind of arc from the leads, no matter which function you have selected! Any half decent DMM should be able to handle its full voltage rating on any voltage range, AC or DC, ohms, continuity, diode check, and any other mode it has, without any damage to the DMM itself or the leads.

Basically this means your DMM is a piece of junk. It's either defective or poorly designed. You get what you pay for.

--- End quote ---

I didn't pay for it. It was free. The product description says it will measure down to 1mA AC current. I put a 12W bulb in a fixture and used the clamp. My volts are right at 120V. It did it.

It measured exactly .101 amp.



DW1961:

--- Quote from: helius on July 25, 2020, 10:24:17 pm ---The "wire with a little bead on it" is a K-type thermocouple wire. It is designed for high-temperature use and isn't going to just melt (although the heatshrink could).

If your meter only reads AC amps using the clamp, it is unlikely to have any fuse.

--- End quote ---

Just got this back from teh Amazon merchant:

"I received this replay back fro the seller on Amazon, for what it's worth. He is saying it has both current and voltage fuses in it:

"Our products are equipped with professional voltage and current fuses. In case of misoperation and exceeding the maximum voltage/current range, the fuse will be blown first, and then the circuit board will be destroyed."

F-it! I can tear it apart and see if it really does?! It might be interesting. If it has fuses, I'm assuming it has a way to change them. I'll ask the merchant.

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