Voltech AT5600, Руководство пользователя

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C H A P T E R 7 – T E S T S A N D T E S T C O N D I T I O N S
AT5600 User Manual 98-119 issue 14
Page 120
7.16. R2 – DC Resistance Match
Where Used
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.
Measurement Conditions
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.
Choosing Test Conditions
For optimum accuracy and performance, use the test conditions shown in the DC
resistance section of this chapter for each of the two windings.
Choosing Test Limits
The test limits are the specific resistances for both X and Y terminals together with
+ and
– percentage limits.
Use the PC Editor’s ‘Measure’ button (together with a sample part) if you are
unsure of the resistance values.
Please also see
14.6.2 for specific advice on programming the test, and
10.2.18 for test accuracy specification