Perhaps Jim or Al can comment on the issue of UL/CSA standards and shunting/grounding as compared to IEC.
Ngjockey
Ngjockey,
Could you please expand on your question.
I am no expert on UL, just know the basics.
UL like NEC code is bare minimum safety standards.
And in the case of Dan's hum problem as long as the amps are safe to use UL or NEC could care less how they sound.
In fact, if memory serves me right, any current leakage below 5ma is acceptable.
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