[Mgs] Positive ground = more rust?

[Paul Hunt]

I did 32 years in telecoms and that never came up, although the 'sacrificial
anode' thing did.  As I recall all the switching equipment used a +50v supply
and hence a negative ground.  I can't see how a length of copper wire would
lose material with the current flowing in one direction but not the other.
Even with contacts one gets a pit and the other a spike, reverse the direction
and the pits and spike change places, but what do you gain?

PaulH.
  ----- Original Message -----
  ... I have been tought,
  that phone switching equipment like coils and solenoids should be operated
  with the ground connected to the positve power.