"something metal" in the enclosure, or something metal that is separate?
If the "something metal" was like an electrical conduit or something
else that has it's own path to ground, there could be a path between the
ground in your enclosure to the other separately grounded item that goes
all the way through your building to the electric panel. A 0.1v
potential difference between the two might be normal.
If you're measuring 0.1v between two points in your enclosure then yeah
that's weird.
On 3/31/2016 5:24 PM, Josh Baird wrote:
I'm working on a new DC enclosure (steel 19" rackmount cabinet). When
using a DC volt meter, and putting the 'red' lead on a common ground
point (my ground bus, a metal rack rail, etc), and the 'black' lead on
something metal, I'm seeing ~0.1V.
I'm assuming this is bad. On the bench currently, I have the AC
ground connected to my PSU. I have all other devices (switch, surge
suppressors, rack rails, etc) tied to a common ground that isn't yet
connected to earth. My PSU and power distribution is on a metal DIN
rail which in turn is mounted to the metal rack rails.
Should I be concerned with this? As much as I try (or not), I still
have trouble wrapping my head around ground/ground potential/etc.
Josh
