I am working on an old turntable power supply on my workbench. I have acquired a 1:1 bench isolation transformer to increase safety while doing this. It seems to be a well known "issue" with at least the model of transformer I have that the earth ground pin on the 3-prong isolation (output) side is linked to the transformer's chassis-ground and on to the input side (neutral?) and is thus not itself isolated.
My understanding is that this adds risk where risk should be avoided, and some people proactively snip out that earth ground connection from the output pins inside the transformer (effectively disconnecting the earth-ground on the output side and fully isolating the device that's being worked on). Other, simpler isolation transformers don't include a third earth ground pin on either side.
I believe I understand the circuit-completion rationale for this. But what if the device under test has an earth ground pin? Aren't you defeating the safety ground on the device you're working directly on? Is the idea that that no longer matters since its circuit is isolated anyway? Can anyone speak to whether disconnecting the ground pin is as safe, safer, or less safe, or whether once you've done so, you're intended to use it or ground it in some different way? Thanks.
