Bonding Copper to Galvanized Steel
Bonding Copper to Galvanized Steel
(OP)
Gentlemen,
I have a question on bonding copper to galvanized steel.
In all electrical outdoor substations, usually the ground grid buried is COPPER. The substation fence is usually HOT DIP GALVANIZED STEEL. Normally this fence is bonded to the grid using thick COPPER wire to avoid any shock hazards on the fence. In addition to above, the same fence is also in contact with the grid through the SOIL (electrolyte).
1) Does the above setup make a corrosion cell?
2) Is there a possiblity for the fence (nobel material) get corroded and destroy after sometime?
3) How to avoid this?
Your input is appreciated.
I have a question on bonding copper to galvanized steel.
In all electrical outdoor substations, usually the ground grid buried is COPPER. The substation fence is usually HOT DIP GALVANIZED STEEL. Normally this fence is bonded to the grid using thick COPPER wire to avoid any shock hazards on the fence. In addition to above, the same fence is also in contact with the grid through the SOIL (electrolyte).
1) Does the above setup make a corrosion cell?
2) Is there a possiblity for the fence (nobel material) get corroded and destroy after sometime?
3) How to avoid this?
Your input is appreciated.





RE: Bonding Copper to Galvanized Steel
On all the fencing on site the post are encased in concrete.
All the fencing has a bottom taught wire which is where we usually look for any problems. The only problem is that part of the fence is painted with ZRC every so often due to industrial atmospheric corrosion. The ground wires were originally attached with CadWeld at about 6" but the later ones were clamped at the same height.
RE: Bonding Copper to Galvanized Steel
2) The fence is not noble compared to the copper wire - the zinc will be sacrificial to both iron and copper. The zinc coating will corrode over time due to normal atmospheric corrosion, but it may be enhanced locally due to contact with the copper.
3) Probably not necessary, unless you are near a coast and have a highly saline atmosphere.
Regards,
Cory
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RE: Bonding Copper to Galvanized Steel
Regards,
MetCorr