Polarisation

[cytech]

Hi, All

What is the purpose of polarisation coupon in cathodic protection system.

Regards
Cy

[f.ghezeljeh]

polarization coupon and protected structure are from same metal. coupon is insalled in same enviroment and experince same corrosion.
coupn is electrically bonded to structure by bonding box and we have a jumper (remvable link) in this box.
So for potential measurement of structure we can measure potential of coupon
and when coupon and structure is connected this potential will be on-potential
and when we disconnect coupon from structure with link in box this potential will be instant-off potential and
we can check criteria for cathodic protection.