About Loop Resistance Tester

    　Loop resistance tester is also called RX transformer loop resistance tester, English name: Loop Resistance Tester.

 

　　Detailed introduction of loop resistance tester According to the requirements of the new "Electric Power Equipment Handover and Preventive Test Regulations", the test current for measuring the conductive loop resistance of various switchgear shall not be less than 100A. In response to this, our factory has designed and developed a new generation of intelligent loop resistance tester products according to the requirements of the new regulations. This product is suitable for testing the contact resistance value of the main contacts of high and low voltage switches, the DC resistance value of high and low voltage cable lines, etc. The intelligent loop resistance tester adopts 100A constant current output. The maximum output voltage is 10V (2-3 times that of conventional instruments). Thin test wires can be used, which greatly reduces the labor intensity of on-site testers. The test process is all automatically implemented by single-chip control, with high accuracy, good reproducibility, single-button operation, simple and easy operation, and LCD display of test data. Suitable for different working environments.

 

　　The machine has a built-in 100A switching power supply, which enables it to achieve a constant current of 100A and two sets of loops for real-time tracking testing, ensuring the correctness of the test results.

 

　　It 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 DC 100A recommended by national standards.

 

　　The resistance of the conductive circuit of a high-voltage circuit breaker mainly depends on the contact resistance between the moving and static contacts of the circuit breaker. The existence of contact resistance increases the loss of the conductor when it is energized, and increases the temperature of the contact. The value of the contact resistance directly affects the current carrying capacity during normal operation and affects the short-circuit current breaking capacity to a certain extent. Therefore, the resistance tester value of each phase conductive circuit of the circuit breaker is an important data for the installation, maintenance and quality acceptance of the circuit breaker. 

2. Types and Uses

　　Loop resistance tester: Ground resistance meter purpose and application scope: Ground resistance is suitable for directly measuring the ground resistance value of various grounding devices, and can also be used for general low resistance measurement. The four-terminal button (0~1~10~100Ω specification) can also measure soil resistivity.

 

　　Loop Resistance Tester: Single Clamp Loop Resistance Tester

 

　　Single clamp loop ground resistance tester performance and features: Unique single clamp design can avoid the error of mutual interference between the two probes of double clamp type. No need to drive auxiliary ground stakes, just clamp it and measure.

 

　　Loop Resistance Tester: Universal Ground/Insulation Resistance Tester

 

　　There are many testing methods: double clamp ground resistance test, four-pole ground resistance test, soil resistivity test, insulation resistance test, AC/DC resistance tester pressure test, and current effective value test.

 

　　Loop Resistance Tester: Ground Impedance Tester

 

　　When measuring with the clamp-type ground resistance meter series, there is no need to use an auxiliary ground rod, nor to interrupt the grounding of the equipment to be tested. Just clamp the ground wire or rod, and the ground resistance can be measured up to 0.1Ω. It can also measure current.

 

　　Loop Resistance Tester: Loop Resistance Tester

 

　　Microprocessor control for high accuracy and reliability. Three indicator lights to check if the wiring is correct. Direct reading of short circuit protection current and ground fault current. Automatic lockout when the test resistor is overheated.

 

　　Loop resistance tester: digital ground resistance tester

 

　　This tester is specially used to measure the grounding resistance value of various electrical equipment, lightning rods and other grounding devices. The product is a fully electronic instrument, and the key circuit is assembled from integrated circuits produced by Texas Instruments, USA. The test principle is advanced.

 

　　Loop resistance tester: double jaw ground resistance tester

 

　　It has a variety of ground resistance measurement methods: no auxiliary pole/three-pole/four-pole/single-pole method－－－－suitable for a variety of measurement environments*Wide measurement range: 0.002Ω—300KΩ－－－－meets a variety of requirements.

 

　　Loop Resistance Tester: Ground Resistance Tester 

3. Working Principle

　　The loop resistance tester uses a pulse width modulated high-frequency switching power supply to provide a test current greater than 100A. When the measurement key is pressed, the high-frequency switching power supply outputs a test current greater than 100A. At the same time, the sampling circuit starts sampling, and the obtained signal is amplified by the amplifier. After the A/D converter converts the analog signal into a digital signal, the microprocessor filters, calculates, and processes the data, and finally sends it to the display to display the measured current and resistance value. After displaying for 10 seconds, the system automatically resets. When the measured loop resistance value is less than 400μΩ, the minimum measurement resolution is 0.1μΩ, and when the measured loop resistance value is greater than 400μΩ, the minimum measurement resolution is 1μΩ.

 

Operating Procedure

　　⒈ Connect wires according to the four-terminal method.

 

　　⒉ Turn on the power.

 

　　⒊ Press the measurement key (if the current displayed A value is less than 100A, it can be corrected through panel current fine-tuning).

 

　　⒋ After measuring the displayed value, the data needs to be saved.

 

　　5. After the measurement, please turn off the power.

 

　　⒍ Please take good care of the test pliers.

 

Technical Parameters:

　　Measuring range 100A 0-3000uΩ

 

　　200A 0-1500uΩ

 

　　Measuring accuracy: 0.5 level

 

　　Display mode: LCD display result printing

 

　　Working voltage: AC220V

 

　　Working principle: sampling - amplification - holding - A/D conversion - microcontroller processing -

 

　　Output: Display and Print

 

　　Appearance structure: Standard chassis with compact structure, power input socket and power switch are at the bottom of the instrument