Voltech AT5600, Руководство пользователя

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C H A P T E R 1 4 - A T E D I T O R
AT5600 User Manual 98-119 issue 14
Page 330
14.6.11.
TRL - Turns Ratio (by Inductance)
The TRL test measures the turns ratio between a pair of windings by comparing
their inductance. This is different from the TR test, which compares the voltage
used to energize one winding, with the voltage induced on a second. The TRL
test is preferable to the TR test when the coupling between the primary and
secondary windings is poor.
An alternating voltage is applied to each winding in turn. The alternating currents
that flow and the applied voltage at the transformer are measured. From these
measured currents and voltages, a complex-impedance is derived, and the
inductance is then calculated. The turns ratio is computed by dividing the square
root of the primary inductance by the square root of the secondary inductance.
On selecting ‘TRL Turns Ratio (from inductance)’ from the available tests window,
a dialogue box will be displayed.
To program the test:
1. In the fields provided, insert the voltage and frequency you require for the
test (see chapter 7 - ‘Test Conditions’).
2. Select (mouse click the button) the integration time you require.
'Medium' is the default setting. 'Long' will give more stable readings (for
tighter limits) at the expense of an increased test time, and 'Short' will test
at the maximum speed, but may give a slightly noisier reading. See 7.3
Explanation of Integration.
3. Select the high and low terminals of the primary winding. (Click on the
arrow to the right of the fill-in box and you will be provided with a choice of
the available terminals. Click the required terminal.)
Select the high and low terminals of the secondary winding.