Al A. wrote:

On Wed, 13 Jul 2005 15:35:36 -0500, "Robert Swinney"
wrote:
I recall

reading that early watt-hour meters were electrolytic devices. Not sure how
they worked, though. Maybe someone can help.

Boib Swinney




I may not remeber this 100% correctly, but I seem to recall reading
that at one point, one type of meter was a sort of electrolytic cell
with copper bars in it, in which as the customer drew power from the
line, it would cause material to be plated onto the copper bars.
Periodically, the "meter reader" would drop by and weigh the rods to
determine how much to bill the customer. Drawing a blank on the
details and source, so this could be all wrong. G

I've heard of such a thing.

A lot of old Sony pro video gear had hour
meters that worked on the same principle.
A little glass cartridge about the size of
a 3AG fuse with a bead of metal that would
move over time when current was applied.
They were good for 1000 hours and then could
be flipped around for another 1000 hours.