These instruments are used for Measurement of DC resistance values of transformer windings, rotating machine windings, or any D.C. resistance of inductive devices. 

The measurement of the DC resistance of the transformer windings and comparison to the design calculations verifies that the correct conductor size has been used, brazed, crimped or bolted connections are satisfactory and that the contact resistance of any tap switches or tap changer is within acceptable limits.

Scope TRM-25