Hello!
I'm having a strange behavior with my BM235, and I'm wondering if anyone would have insight on why it would be happening.
I have a circuit with mosfets and diodes in parallel, and they're all facing the same direction. On the BM235, when I test the circuit, I'm getting 0.424V in one direction and 2.552V in the other direction. This lead me to try to test the board with a thermal camera and current going through the board thinking that it was a busted diode (or body diode), and I wanted to see which one it was, but it didn't allow any current through.
After testing the board and getting nothing, I tried different multimeters to see if the same thing happened on other meters. On the Fluke 87V from work, it showed an open circuit. On my Sanwa PM300, it's showing open circuit, and on my AMECaL ST-9927T, it's also showing an open circuit.
I'm seeing that the Fluke 87V seems to test at 1mA at 3V (I could be wrong about this one), the BM235 seems to test at .3mA at 3V, and the AMECaL is at 2.7V (maybe 2V) based on the FS9922-DMM4 datasheet. It didn't list a current - just that it should have a 1K resistor. The Sanwa advertises a 3.2V open circuit voltage.
For fun, I also tested the voltage that the AMECaL was testing at to see if it wasn't as high. It was measuring at 2.6V, which is above the 2.552V, but not by much. The Sanwa was measuring at 2.987V. I'm not at work at the moment, so I can't measure the Fluke 87V.
Is there something different about the way that the BM235 measures diodes that it's picking up on something? Is it a faulty device? I tried testing a new board that didn't have the same potential for failure, and the BM235 and other meters had the same behavior. edit for clarity: the BM235 had the same weird behavior. They didn't all do the same thing on the other board.
Thanks!