I was watching a video on youtube they talked about grounding, isolation, and GFCI type devices.
They mention one thing I never thought of which is that with isolation GFCI devices are useless. Isolation protects from a normal shock, but if you got across both isolated output there's no protection even from a GFCI on the primary side. They said this is why if testing live gear you should use the one hand rule. I understand this, but brought up interesting question.
In theory at least it seems it would be better to be unisolated and behind a GFCI. May be a bit more risk of shock, but it would be minor either way. Whereas if were isolated and contacted both you have nothing except a fuse or breaker. I know neither are perfect, but GFCI seems the lesser of the evils for most cases.
Say you were testing some live gear what method would you trust more?
They mention one thing I never thought of which is that with isolation GFCI devices are useless. Isolation protects from a normal shock, but if you got across both isolated output there's no protection even from a GFCI on the primary side. They said this is why if testing live gear you should use the one hand rule. I understand this, but brought up interesting question.
In theory at least it seems it would be better to be unisolated and behind a GFCI. May be a bit more risk of shock, but it would be minor either way. Whereas if were isolated and contacted both you have nothing except a fuse or breaker. I know neither are perfect, but GFCI seems the lesser of the evils for most cases.
Say you were testing some live gear what method would you trust more?
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