2.13 R2 - DC Resistance Match
The DC resistance match test, as opposed to an ordinary DC resistance
measurement (R) - is used on audio and telecommunications transformers,
where it is important that the resistance of different pairs of windings
is controlled and matched to a specified ratio.
The absolute value of the resistances may be of less importance to the
performance of the transformer than the match between two resistances.
To measure DC resistance match, the tester makes two DC resistance
measurements (see the R test) and compares the two results.
Limits for the match of the two measured resistances may be set in terms
of the ratio between them (e.g. 1:1 +/- 5%).
By adding further DC resistance match tests to the test program, any
number of DC resistances can be tested for match.