Digital Circuit Breaker Analyzer and Micro-Ohmmeter: Integrating Mechanical Characteristics and Micro-Ohm Measurement
In power systems, circuit breakers serve as the last line of defense for equipment and personal safety; the contact status of their moving and stationary contacts directly determines whether the equipment can reliably interrupt fault currents. The digital circuit breaker analyzer and micro-ohmmeter is a professional testing device designed specifically for this purpose, using "static + dynamic" two-dimensional testing to ensure that circuit breaker performance meets factory standards.
I. Contact Resistance Measurement: The Core of Static Circuit Testing
Contact resistance is a key indicator for evaluating the performance of a circuit breaker's conductive circuit. According to standards such as IEC 62271 and DL/T 845.4-2004, the contact resistance of circuit breaker contacts must be strictly controlled within specified limits. If resistance increases abnormally, the temperature at the contact points will rise sharply when the equipment carries rated current, potentially leading to contact burnout or even explosions.
The micro-ohmmeter employs the four-wire Kelvin bridge principle to eliminate the influence of lead resistance: a pair of current leads applies a high DC constant current of 100A or higher to the circuit under test, while another pair of high-impedance voltage leads directly measures the minute voltage drop generated as the current flows. The instrument automatically calculates the resistance value using the formula R = U/I. Goldhome's HM6090S-100A handheld contact resistance tester can output a DC test current of 100A, with a measurement range of 0.1 μΩ to 2 mΩ, a resolution of 0.01 μΩ, and an accuracy of ±(0.5% + 2 digits). Test durations can be selected from 1s, 10s, 30s, or 60s. This device is specifically designed for micro-ohm-level contact resistance testing of main contacts in SF6 circuit breakers, vacuum circuit breakers, and isolating switches. Weighing only 1 kg, it can perform ≥100 switching measurements on a single charge and supports multi-range current adjustment from 30A to 100A. It fully complies with the requirements of the DL/T845.4-2004 standard and is suitable for on-site maintenance and factory acceptance testing.
II. Mechanical Characteristics Analysis: Comprehensive Diagnosis of Dynamic Operation
During long-term operation, mechanical components of circuit breakers may develop hidden issues such as wear or sticking. The circuit breaker analyzer simulates actual operating conditions to drive the circuit breaker's operation. High-precision sensors capture dynamic parameters including closing/opening times, synchronism, speed, overtravel, and coil current waveforms. An embedded processor automatically compares these against factory standards and provides a "Pass/Fail" determination. Goldhome's HM6080 High-Voltage Switch Characteristic Tester uses an ARM7 core for sampling, processing, and output, capable of simultaneously testing the inherent closing and opening times of 12 contact points, as well as phase-to-phase and phase-to-phase synchronization. This instrument is suitable for various types of high-voltage switches, including SF6 switches, GIS (Gas-Insulated Switchgear), vacuum switches, and oil switches, and supports flexible configuration of multiple speed/distance sensors (linear and rotary sensors). Its strong resistance to electromagnetic interference allows for precise measurements even under live conditions on the bypass busbar of a 500kV substation, meeting the demands of various complex field environments ranging from substations to power plants.
Goldhome: A Professional Supplier Dedicated to the Circuit Breaker Testing Field
Goldhome Hipot established in 2008 and located in the Wuhan Economic and Technological Development Zone, is a national-level high-tech enterprise integrating R&D, production, and sales. It has been honored with the titles of Wuhan "Science and Technology Little Giant" Enterprise and "Gazelle Enterprise."
In the circuit breaker testing field, Goldhome offers a full range of solutions, from handheld micro-ohmmeters to full-featured circuit breaker analyzers. Regarding the micro-ohmmeter product line, the HM6090S-100A handheld contact resistance tester is specifically designed for measuring contact resistance and loop resistance in high- and medium-voltage switches. It supports testing of main contacts in SF6 circuit breakers, vacuum circuit breakers, and disconnect switches, delivering a constant DC current of 100A with a resolution of 0.01μΩ. weighing only 1 kg with dimensions of 200 mm × 100 mm × 60 mm, making it ideal for mobile on-site testing in outdoor substations, wind farms, and railway applications. Regarding circuit breaker analyzers, the HM6080 series can simultaneously measure mechanical characteristic parameters of 12 contact points. It supports graphite contact models (HM6081A), is equipped with various speed sensors, offers excellent anti-interference capabilities, and features comprehensive data storage and printing functions. Goldhome strictly adheres to domestic and international standards such as IEC 62271 and DL/T 845.4. Our products are exported to over 30 countries and regions across Europe, America, Africa, the Middle East, and Southeast Asia, and we are committed to providing precise and reliable testing solutions to ensure the safe and stable operation of power systems.
