Hi All. I just received my 121gw meter on Friday and was playing around with it today and found something that was not working as I expected. It's probably just operator error so I was hoping that someone could possibly explain what's going on.
Ok, I was just doing a basic current measurement. Input voltage is 5v, resistance is a smidge over 300 ohms (300.03). That coupled with the sense and fuse resistance of 1.3ohms should give me a 16.6mA.
So I preformed the measurement and the meter set in DC Auto returns a measured value of 83.55mA in the 500mA range with a burden voltage of 2.6mV. This is obviously incorrect. So I tried the 5A and 10A range. Both of these ranges were correct and returned a value of 16.6mA. So what's going on? Am I doing something wrong? I checked the manual and I must admit that the diagram showing how to measure the current and burden voltage on page 41 is a little confusing it shows no relationship to the power supply and if the load is connected on the high or low side of the common connection. The arrow indicating the current direction is also confusing.
I'll attach some photos which I hope will make things clearer.
I have also installed the v2.0 firmware.
Regards
Stuart
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