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 140
7.30. SURG - Surge Stress Test
Where Used
This test may be used to detect a short circuit between adjacent turns in a
winding. It is applicable to any transformer but is particularly suitable for
transformers with many turns using very fine wire.
For such wire, the enamel coating is very thin, and there is a danger that it will be
scratched giving rise to exposed copper. In some cases, the scratch does not
immediately cause a shorted turn, but will leave a weak spot which may
eventually fail. A higher than normal test voltage is used to help find faults which
may occur later in use.
Measurement Method
Each SURG test can be programmed to consist of many DC impulses.
It is recommended to use a small number of impulses (normally 3) to
demagnetize the core before taking the reading from the last impulse.
More impulses may also help find defective wire insulation.
For multiple impulses, The AT5600 will return the LOWEST result of all the
impulses programmed.
For each impulse, the AT5600 will charge an internal capacitor to the
programmed test voltage. This stored DC charge will then be suddenly
discharged into the part under test and the resulting transient voltage will be
analyzed. The surge result is the area under the waveform curve. A typical
transient waveform is shown below