At test sites for transformer windings, motor coils, or switch contact resistance, design and selection engineers often need to balance measurement range, power supply method, and reading efficiency. The following Q&A provides reference from the perspective of engineering parameters.
The KDZ-20A DC resistance tester has a measurement range of 0–20 kΩ and is suitable for DC resistance measurement of inductive loads such as transformer windings, motor windings, and relay coils. It can also be used to detect the contact resistance of switches and circuit breakers. The instrument uses AC power supply and is suitable for continuous use in fixed production sites such as assembly lines.
The instrument has a built-in microcontroller that handles range switching, data acquisition, and logic processing. The display uses a 3 1/2-digit LED digital tube, providing intuitive readings that are clearly legible under lighting conditions in workshops or laboratories. The unit weighs about 3 kg, making it easy to move between workstations or install fixedly on a test bench.
To meet assembly line takt requirements, the instrument optimizes the measurement sequence, allowing a single measurement to be completed in a relatively short time and meeting the efficiency needs of batch testing. Microcontroller control reduces manual intervention and provides good measurement repeatability. The AC power supply method eliminates battery replacement and charging management, making it suitable for long-term online testing.
Selection engineers should confirm whether the maximum resistance value of the object under test is within the 0–20 kΩ range and evaluate whether the on-site power supply conditions match the AC power supply requirements. If used for switch contact resistance measurement, attention should be paid to whether the test current meets the testing specifications of the contact under test. The instrument is not suitable for resistance measurement beyond its range, and long-term use in environments with strong electromagnetic interference or high humidity is not recommended.
