Connect all high and low voltage current and potential test lines to the transformer at once; no need to switch test lines during the test.

For star-connected winding tests, the instrument can test the resistance of phases A0, B0, and C0 simultaneously in a three-phase test, saving test time.

When testing a three-phase five-limb transformer with a low-voltage internal delta connection, the instrument uses an automatic magnetic assist method internally, which is faster than directly using a large current for testing.

Display and print all test data for the high, medium, and low voltage windings of the transformer, automatically calculate the three-phase unbalance, and also print the resistance value converted to the rated temperature.

During three-phase testing, first test the A0 data, then test all three phases simultaneously, solving the problem that the neutral point lead resistance cannot be tested during simultaneous three-phase testing, making the test data closer to single-phase test values.

Inductive load DC resistance tester

The instrument should be reliably grounded. After connecting the test lines, turn on the power. During the output current test, do not remove the test lines to avoid accidents. After completion, wait until the current arc suppression indication ends or the audible and visual alarm stops before turning off the power and removing the test lines.

When using the three-channel method to measure an on-load tap changer transformer, the tap changer can be switched under load, saving charging time.

When measuring an off-circuit tap changer transformer, wait until the discharge indication alarm stops before switching the tap changer or changing the gear.

The magnetic assist test is mainly for three-phase five-limb transformers with a delta-connected low-voltage winding (if the low-voltage winding is found to be delta-connected and charging is slow during the test, the magnetic assist method can be used).

Wiring and Operation

1. Connect the instrument to an external AC 220V power supply using the power cord, and connect the grounding terminal to the earth using the grounding wire.

2. When testing a two-winding transformer, connect the four test clips (yellow, green, red, black) of the high-voltage test line to the A, B, C, and O bushings on the high-voltage side respectively. If there are only three bushings (A, B, C), the black test clip can be left floating; connect the other end of the test line to the corresponding terminals on the instrument. Connect the four test clips (yellow, green, red, black) of the low-voltage test line to the a, b, c, and o bushings on the low-voltage side respectively. If there are only three bushings (a, b, c), the black test clip can be left floating; connect the other end of the test line to the corresponding terminals on the instrument.

Note: No need to switch lines during the entire test process.

3. For a three-winding transformer, after testing the high and low voltage windings, connect the four test clips of the high-voltage test line to the medium-voltage side for testing.

4. For a single-phase transformer, connect the yellow and black test clips of the high-voltage test line to the high-voltage side of the single-phase transformer, and connect the yellow and black test clips of the low-voltage test line to the low-voltage side of the single-phase transformer.

5. The instrument is equipped with