In routine testing of zinc oxide arresters on 10kV distribution lines, procurement personnel often face a choice: whether to continue using traditional pointer-type DC parameter testing schemes or to adopt digital display testers with three-phase automatic compensation. The two differ significantly in wiring efficiency and data repeatability. Traditional schemes require phase-by-phase measurement and manual recording, taking about several minutes per arrester; while discharge tube testers supporting three-phase simultaneous testing can obtain three sets of data with one wiring connection, reducing errors caused by repeated disconnection and reconnection of leads.
From the perspective of on-site adaptability, the difference between high-speed magnetic isolation digital sensors and ordinary optocoupler isolation schemes lies in their electromagnetic interference resistance. The former, when the arrester is adjacent to live compartments, can suppress the impact of ground potential fluctuations on the sampling channel, maintaining accuracy within ±2%. For buyers, if testing tasks are concentrated in substation switchgear cabinets with complex electromagnetic environments, digital isolation schemes can reduce the number of retests caused by interference, indirectly saving labor costs.
Power supply and battery life are also practical indicators in procurement comparison. The built-in power supply takes 2 to 3 hours to charge and can work continuously for more than 8 hours, covering testing tasks for multiple compartments in a single day without the need for on-site external AC power. Compared with schemes requiring external inverters or long-distance power cables, it reduces the number of accessories to carry and wiring steps, making it suitable for outdoor or switch room corridor operations without fixed maintenance power sources.
