TESTER, DIGITAL PHASING 240KV, To easily determine phase relationships, these CHANCE Phasing Testers read approximate voltage (line-to-line or line-to-ground) on transmission circuits. The testers consist of two high-impedance components encased in fiberglass poles, each with an end fitting threaded for interchangeable hook probes. A 22-foot-long insulated flexible cable from the voltmeter stores on a reel on the other pole.