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 such as 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. To this end, 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 test current for measuring contact resistance of circuit breakers and disconnectors shall 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 and digital circuit technology. The HL-100A loop resistance tester is suitable for measuring the loop resistance of switch control equipment. Its test current adopts DC 100A recommended by national standards. The loop resistance can be directly measured at a current of 100A and displayed digitally. This loop resistance tester has accurate measurement and stable performance, meeting the requirements for on-site high-voltage switch maintenance by power and supply departments and 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 is warranted for two years, with lifetime maintenance responsibility.