Re: Oscilloscope
A groundloop is when current takes detour through another potential lower resistance ground path other than the designed ground path of a circuit or device.
For example: AC electricity coming from the hot side passes through a PSU that you are testing, it becomes current or load and is returning to the source via neutral/ground. When you probe the PSU, your scope probe has the potential to ground a component out which might create a electrical short. The current has a potential to shift to the probe due to lower resistances than the designed neutral/ground path and it passes through the scope which electrifies the chassis which kills you or destroys the scope and blows up the PSU.
That's the reason why you need an isolation transformer, to isolate your test-subject from the structure wiring while providing a permanent power solution. If you don't have one then as Th3_uN1Qu3 said, battery backups or inverters connected to some deep cycle batteries will work just as long as you unplug the charger or battery backup from the structure wiring and have enough run-time to do the tests.
One thing I don't know for sure is, do you plug the scope into the isolation transformer too or not? I don't have a scope, but this thread has been an interesting read.
A groundloop is when current takes detour through another potential lower resistance ground path other than the designed ground path of a circuit or device.
For example: AC electricity coming from the hot side passes through a PSU that you are testing, it becomes current or load and is returning to the source via neutral/ground. When you probe the PSU, your scope probe has the potential to ground a component out which might create a electrical short. The current has a potential to shift to the probe due to lower resistances than the designed neutral/ground path and it passes through the scope which electrifies the chassis which kills you or destroys the scope and blows up the PSU.
That's the reason why you need an isolation transformer, to isolate your test-subject from the structure wiring while providing a permanent power solution. If you don't have one then as Th3_uN1Qu3 said, battery backups or inverters connected to some deep cycle batteries will work just as long as you unplug the charger or battery backup from the structure wiring and have enough run-time to do the tests.
One thing I don't know for sure is, do you plug the scope into the isolation transformer too or not? I don't have a scope, but this thread has been an interesting read.
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