n8wrl,

Something like you describe. Without asking Tom, our engineer, I'm not sure what it exactly does, but it does not endanger anyone in terms of electrical shock (like putting a "cheater" on a 3-way plug does). I don't think there is a ground-lift screw on the 350.

Glad you solved your problem.

Regards,

Alan Lofft,
Axiom Resident Expert (Retired)