Maintenance and Repair of 100A Loop Resistance Tester

Currently, in the measurement of contact resistance in power systems, the conventional QJ44 double-arm DC bridge is commonly used. However, the test current of such bridges is only in the mA level, making it difficult to detect defects caused by reduced cross-sectional area of loop conductors. When measuring the contact resistance of high-voltage switch conductive loops, due to the influence of oil film and oxide layer between contacts, the measured value is several times larger, failing to truly reflect the contact resistance value. Therefore, the Ministry of Electric Power standard SD301—88 "AC 500KV Power Equipment Handover and Preventive Test Procedures" and the new edition of "Preventive Test Procedures for Power Equipment" stipulate that the measurement current for contact resistance of circuit breakers and disconnectors should not be less than DC 100A, to ensure accurate test results.

The loop resistance tester is designed based on the latest power execution standard DL/T845.4-2004 of the People's Republic of China, combining high-frequency switching power supply technology with digital circuit technology. The HL-100A loop resistance tester is suitable for measuring the loop resistance of switch control equipment. Its test current adopts the DC 100A recommended by national standards. It can directly measure the loop resistance at a current of 100A and display it digitally. This loop resistance tester has accurate measurement, stable performance, and meets the requirements of on-site high-voltage switch maintenance in power and supply departments, as well as loop resistance testing in high-voltage switch factories.

Maintenance and Repair: 

The instrument should be stored in a well-ventilated, dry, cool, and clean place, with attention to moisture prevention and protection from corrosive gases. The product has a two-year warranty and lifetime maintenance responsibility.