checking dc current in ac installation

[mackos]

how do you check if you have DC current in CU for the purposes of saturating a type AC RCD causing it to malfunction.Thanks Mack.

 

[Lucien Nunes]

Presumably you are only interested in the differential current (or its DC component) rather than the normal circuit current. Therefore, if you want to measure without interrupting the main circuits you would need a sensitive DC-compatible current probe, e.g. a Hall-effect type rather than a transformer type. You could display the output on a scope to observe the offset between AC and DC coupled readings, or possibly just read them with a multimeter (depending on its sophistication.)