Product Details

In power systems, the conventional QJ44 double-arm DC bridge is commonly used to measure the DC resistance of transformer windings and the contact resistance of high-voltage circuit breakers. 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 conductors in transformer coil conductive loops. When measuring the contact resistance of high-voltage switch conductive loops, due to the influence of oil film and oxide layers between moving and static contacts, the measured resistance value is several times larger, masking the true contact resistance value. Therefore, the Ministry of Electric Power standard SD301—88 "Regulations for Handover and Preventive Tests of AC 500kV Electrical Equipment" and the new edition of "Regulations for Preventive Tests of Electrical Equipment" stipulate that the measurement current for contact resistance of circuit breakers and disconnecting switches shall not be less than 100A to ensure measurement accuracy.

100A Loop Resistance Tester is designed by combining digital circuit technology and switching power supply technology. It is suitable for measuring contact resistance and loop resistance of switch control equipment. Its test current adopts the DC 100A recommended by national standards. It can directly measure loop resistance and contact resistance at a current of 100A and display them digitally. This instrument features accurate measurement and stable performance, meeting the requirements of on-site high-voltage switch maintenance in power and power supply departments and loop resistance testing in high-voltage switch factories.