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Multimeters that do not appear to meet their safety specs.

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DT832 from an unknown Chinese manufacturer.
On the front panel I read: 200 mA MAX. On the PCB near the fuse: 0.5 A 250 V.
Now the fuse itself. A miniature fuse (approx. as a germanium diode), but its filament looks WAY too thick. No marking at all.
Several AA batteries, a 10 A meter, this fuse...
2.5 A: no reaction at all.
4 A: no reaction, only some heat.
4.6 A: the filament starts glowing red, but does not melt. 30 seconds (I couldn't resist that heat any more) - no melting.
The resistance of test leads did not allow me to push higher currents into the fuse.
Then... FIVE!!! AA alkaline batteries in series (typically ~10..12 A short-circuit current), a piece of thick wire, no meters. The fuse tripped in TWO SECONDS!
Is it a 5 or 6 A fuse? A slow-acting fuse typically melts in several seconds at 2x load. A 0.5 A fuse should melt in two seconds at 1 A, not 10 A.

WHY??? Now it's unsurprising that the first thing burning in these meters is the PCB or resistors on it, then the ADC chip, the switch contacts, but not that damn fuse.


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