ISA T 2000 - Power Transformers Tests; 1: PT Tests: Ratio Per TAP

DOC. MIE11110 Rev. 5
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. Protection timing: Set the knob a little higher than the position
corresponding to the threshold, and start the test: as the current
is interrupted, the timer displays the elapsed time.
An automatic counter is increasing as you repeat the tests on the
three phases.
1.3: POWER TRANSFORMERS TESTS
When this test is selected, the following menu is displayed.
It is possible to select the tap number: this selection is reported in
the two available tests, i.e. ratio and resistance of tap changer
contacts.
1.3.1: PT tests: ratio per TAP
When this test is selected, the following menu is displayed.
Purpose of the test is to verify that the ratio is correct on all
available taps. The tap number, selected in the former window, is
displayed above.