A terminal box on a post or flush with grade where test leads welded to the pipe, coupons, casings or foreign lines come to the surface. CP techs take pipe-to-soil potentials there, measure line current and check bonds and isolation. Pipelines typically place them about every mile and at road and rail casings, insulating joints and foreign line crossings.
Test station at MP 22 got hit by a mower again, the leads are cut and we can't read the casing.
Agree a wire color code for pipe, casing, coupon and foreign leads and stick to it system-wide; it saves hours of guesswork at every post.
Also heard as
- test post
- test point
- TS
Related terms
Pipe-to-soil potential
Voltage between a buried pipe and a reference electrode on the soil surface, the basic CP measurement.
Cad weld
Shop name for an exothermic weld, the thermite connection used to attach CP cables to pipe and anodes.
Bond
Wire or cable connection that ties two metal structures together electrically, often to control CP current.
CP coupon
Small bare steel sample buried beside a pipe and wired to it, used to read IR-free potentials.