I bought this from Unitop for PHP 240, it is a cheap digital clamp multimeter. It has Current Range from 0~400A AC, 450V DC voltmeter, Continuity/Diode Test Buzzer and Ohmeter 200K.
The model says MT87, it needs 2x AAA Battery Cell, it has a box, instruction manual and two wires for testing circuits. This model can also be found on Lazada but the price
is a bit more than this. The clamp meter also has a Data Hold function, which when pressed, displays the current data from LCD screen until you press it again to reset.
Measuring AC voltage
The problem with this device is the polarity of the voltmeter, if I measure a battery in reverse. It does not display a minus sign to indicate a reverse polarity.
I tested the ammeter functionality using a water heater and it works. It shows about 4.4 amps, the nominal voltage in my country is 220~250V so, the water heater rated 1000 watts actually consumes 1100 watts (Power = Voltage x Current).
Current of the water heater:
The water heater:
I removed the casing to check the internals of the device, there are alot of SMD components, two LM358 op-amp and the black blob IC. I do not see any fuse.
There is the piezo buzzer for the continuity test, I took note of the SMD resistor values. So, when I messed up and ended up damaging this device, I can possibly replace a blown resistor, if possible.
A video about the test and unboxing will be published later.
UPDATED:
https://tube.22decembre.eu/videos/watch/634d25f3-6958-4b0e-b933-cbfc42f1beb9
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