The MTO210 Transformer Ohmmeter is a line-operated, field-portable instrument designed specifically to measure the dc resistance of all types of magnetic windings safely and accurately. It can test transformers and rotating machine windings and perform low-current resistance measurements on connections, contacts and control circuits.

The dual set of potential inputs measures the resistance of the primary and secondary windings of a single- or three-phase transformer simultaneously. This dual reading, dual injection characteristic, also helps to speed up the measurements when used to test LV windings on large three-phase power transformers.