“Demagnitize” Tab

To eliminate the residual flux of a transformer, the demagnetize tab is used. For example, after executing a DC resistance test, it is generated in the transformer. Demagnetizing is done in such a way that a DC current is injected in steps and decrements in direct and reverse directions to each phase of the transformer.

The amount of injection current is entered in “I Test” field.

In “Test Method”, the test method is determined as single-phase or three-phase. By changing this section, the wiring changes as shown on the right of the page.

It’s specified in “Side” field to perform the test on the transformer. By changing this section, the wiring changes as shown on the right.

In “Phase”, each of the phases A, B and C can be specified for testing. By changing this section, the wiring changes as shown on the right of the page.

In “State Time”, the time of each state to change the current is specified.

After configuring the wiring in accordance with the picture, to execute the test, first press “Init Test” button, then run the test. In “Signal View”, the injected current and the actual current value are displayed; this current value turns zero as soon as the demagnetization is completed.