RE: [CAD_CAM_EDM_DRO] Re: Remember Mr. Bill's servo lite?

Conductors (wires) are not perfect; there is always a small amount of
resistance. When current flows through a wire there will be a voltage drop
across this resistance, add in the myriad of connections as wires make their
way from outlet to outlet in your house and visualize all these different
voltage drops across the various bits of wire and you can start to see that
neutral will never be at ground potential (but it should be close). This is
why we bother with the third 'ground' conductor, since it is not used to
carry current it should always be very close to ground potential and provide
a low impedance path to ground.



All DC power supplies are not tied to ground. How and why they might be can
get complex. Grounding of the negative side of a DC supply is typically done
to provide to provide a low impedance path to earth (for noise immunity).



Jeff



From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Andy Wander
Sent: Saturday, January 14, 2012 9:29 PM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: RE: [CAD_CAM_EDM_DRO] Re: Remember Mr. Bill's servo lite?





Now I'm intrigued. Since the neutral line is attached to same exact ground
bus bar in most electrical panels, what could make it "not" stay at or near
ground potential?

I agree on the potential for problems if you use a bridge rectifier, but
again, if you are going to be grounding one side of the DC supply anyway,
then what is it that causes the danger?

Andy Wander






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