At present the contact resistance measurements of the conventional type QJ44 arms widely used in electric power system dc bridge and this kind of bridge test current mA level only 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.Therefore the standard sd301-88 ac 500kV power equipment handover and preventive test regulations and the new version of 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.

Micro Ohmmeter is designed in accordance with The implementation standard DL/ t845.4-2004 of The new Electric Power of The People's Republic of China which combines high-frequency switch The Power supply technology and digital circuit technology.It is suitable for measuring the circuit resistance of switch control equipment.The test current is 100A dc recommended by the national standard.The circuit resistance can be measured directly under the condition of current 100A and displayed by digital display.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 with Micro Ohmmeter、 Resistance circuit tester、 Intelligent Micro Ohmmeter、 Contact resistance meter、 Contact resistance tester、Micro Ohmmeter