This product is a DC resistance tester with the following features: 1. The whole machine is controlled by high-speed single-chip microcomputer, with high degree of automation and simple operation. 2. The instrument adopts brand-new power supply technology, with multiple current ranges and wide measurement range. It can automatically select current according to the load, and is suitable for DC resistance measurement of medium and small transformers and voltage互感器的. 3. The protection function is perfect, which can reliably protect the instrument from the impact of反电势, and the performance is more reliable. 4. With audible discharge alarm, clear discharge indication, reducing misoperation. 5. Fast response speed, can directly convert on-load tap changer in the measurement state, the instrument automatically refreshes the data. 6. Intelligent power management technology, the instrument always works in the minimum power state, effectively reducing the internal heat of the instrument and saving energy.