At present the contact resistance measurements of the conventional type QJ44 arms widely used in electric power system dc bridge and the Test of this kind of bridge current only mA level it is difficult to find circuit conductor cross-sectional area to reduce defects when measuring contact resistance high-voltage switch electric circuit due to the contact between the oil film and the influence of the oxide layer several times the measured value is big can't reflect real contact resistance.To this end the ministry of power standards.88 "ac 500kV power equipment handover and preventive test regulations" and the new "preventive test regulations for power equipment" stipulate that the measuring current of circuit breaker and isolating switch contact resistance is not less than dc 100A to ensure the accuracy of test results.

Contact resistance tester is designed according to The People's Republic of China electric power implementation standard DL/ t845.4-2004 using high frequency switch The power supply technology and digital circuit technology combined.Contact resistance tester is applicable to the measurement of circuit resistance of switch control device.Its Test current USES 100A and 200A dc recommended by national standards.The circuit resistance can be directly measured at the current of 100A or 200A and the final test results are displayed in figures.The instrument is accurate in measurement and stable in performance. It meets the requirements of high voltage switch maintenance and resistance test of high voltage switch factory circuit.

Product names：Contact resistance tester、 switchMicro Ohmmeter、Contact Micro Ohmmeter contact (circuit) resistance tester