UT620A is used to measure DC low resistance through 4-wire method. Its features are: Comparison function to determine if the device is in good condition, unkown wire length calculation (FT/M); two-way data transmission by USB interface. UT620A can be used in narrow space for on-site troubleshooting, such as metal coating resistance, motor and small transformer winding resistance, welding points, power distribution cabinet bus, lead connection inspections, and more.