This lightweight, field portable unit safely and accurately measures the DC winding resistance of all types of transformers and rotating machines. The 830280 Transformer Ohmmeter is extremely useful when testing the operation of on-load tap-changers. This instrument can be used to check the make-before-break operation of on-load tap-changers and also to measure the contact resistance of each tap position.; Resistance measurement range: 2 mohms to 2000 ohms. Test current ranges: 5 mA, 50 mA, 500 mA, 5 A (DC). Two independent measurement channels for simultaneous measurements on two windings. Built-in safety discharge and shut-down feature. Direct digital readout.