Test posts are typically buried along pipelines or pipeline networks to monitor the parameters of cathodic protection. Depending on the service life of the protected pipeline or network, professional technicians are required to measure the protection potential continuously for several years or even decades. Particularly for long-distance pipelines, a test post is installed every few kilometers, often in remote areas without access to municipal electricity. This work is not only labor-intensive but also demands high technical expertise from inspectors (e.g., for test posts with reference electrodes, inspectors need to use multimeters or potential testers along the line; for those without reference electrodes, inspectors must carry multimeters and portable reference electrodes for on-site measurements).
In response to these challenges, our company has developed and produced a new type of solar-powered intelligent potential test post. This innovative test post enables the real-time reception of various parameters related to the protected potential of pipelines or networks from anywhere at any time.
Composition and Structure of the Intelligent Test Post
Product Components: Solar panel, support frame, intelligent potential collector, chemical probe, test post body, power controller, battery, circuit board;
Structural Assembly: The solar panel is fixed to the support frame, which is then secured to the test post housing. The transmission antenna is mounted at the top of the test post housing. The pre-connected programmable controller, analog-to-digital converter, and power controller are fixed onto the circuit board. The assembled circuit board and battery are installed inside the test post housing, which features a small access door. Cables from the pipeline and reference electrode are connected to the analog-to-digital converter. The solar panel, battery, and power controller cables are interconnected, completing the solar-powered intelligent potential test post.
For regional cathodic protection at station sites, it is not recommended to install test posts. Instead, reference tubes should be buried at locations where pipe-to-soil potential measurements are needed to facilitate the placement of portable reference electrodes. Any above-ground metal structure can serve as a contact point for the red probe during measurements. Since all pipelines within the station are interconnected and form an equipotential body, connecting at any point with the station structure will not affect the potential reading.
(1) Test devices should be installed at the following locations:
① Insulating joints;
② Metal casing locations;
③ Connection points of test coupons and drainage grounding devices;
④ Locations of auxiliary anodes and sacrificial anodes;
⑤ Pipeline directional drilling crossing points.
(2) Intelligent test posts should be installed at the following locations:
① Points of pipeline discontinuity (e.g., elbows, phase changes of high-voltage lines, turning points);
② Locations with low soil resistivity;
③ Cathodic protection station drainage points and midpoints;
④ Areas subject to DC interference.
(3) Other important considerations:
① Install potential test coupons every 5–10 km along the pipeline;
② When metal casings have high-quality coatings, leave a 2m bare section at both ends of the casing;
③ Ensure electrical continuity between valve room instruments and the valve body, with the valve body connected to the grounding grid via lightning arresters or DC decouplers;
④ Install surge protection devices at all insulated isolation points.