Using a DMM to measure output isolation/crosstalk| 5 August, 2016
I'm making some PCB's that have some DC to DC converters on them with three 5 Volt converters, one 15 volt converter, and a converter with +/- 12 volts DC. On the PCB the output pins are in a connector that are fairly close to each other. I want to make sure that there is isolation between all the supply outputs. The +/-12 supply shares the same common between them, but I"ll have to check to make sure that common isn't shorted to the +15volts for example. These components were from http://www.kynix.com .
I need to be able to test about 20 of these boards.
My idea is I'm already doing line/load regulation on these supplies so I have the DMM in VDC mode. After the line/load regulation test, I leave the positive lead of the DMM on the first supply, then I move the negative lead to each supply. I should measure the supply voltage output of the first supply, then zero VDC moving the negative lead to each supply.
Then I move on to the next supply leave the positive on that supply, and test all the negative pins making sure they are 0 VDC.
My question is, should I also do this for the positive pins for each supply?
Example: Now leave the Negative lead on the supply, and move the Positive lead to each supply making sure it is also 0VDC, or would this step be redundant?