HZ2611 supports four testing methods, with different types of tested transformers and site conditions corresponding to different optimal choices. Clearly explain the selection logic to avoid data bias caused by mismatched wiring and methods.

Three phase four wire (three watt meter method)

This is the default method when using the HZ2611 built-in inverter power supply, and it is also the most accurate and widely applicable method. Each phase independently collects voltage, current, and power, and the three-phase results are displayed separately, which can detect the asymmetry between each phase.

Applicable occasions:

Use all three-phase transformers with built-in inverter power supply (automatically set by the instrument for this method)

A transformer with a star (Y) connection on the primary side and a neutral point lead out

In situations where it is necessary to check the test results for phase separation to determine the uniformity of each phase winding

Three phase three wire (two watt meter method)

The standard measurement method when using an external three-phase power supply only requires two voltmeters, two ammeters, and two power meters to complete the three-phase measurement.

Applicable occasions:

The primary side is connected in a triangle (Δ) configuration without a neutral point leading out

There is a three-phase power supply and voltage regulator on site, and external power supply is used for testing

Attention: The three-phase three wire method may have certain errors when the three phases are unbalanced, and is not as rigorous as the three-phase four wire method. However, for balanced three-phase systems, the results of the two methods are consistent.

Three-phase phase separation

Use a single-phase power supply to test the three-phase transformer one phase at a time - only test one phase at a time, and record the results separately after measuring the three phases.

Applicable occasions:

Only single-phase power supply is available, three-phase transformer needs to be tested

When suspecting that there is a problem with a certain phase and requiring independent analysis of a single phase

The disadvantage is that the operation is relatively complicated (requiring wiring three times), and the testing time for each phase is different, the temperature may change, and the consistency of the results is slightly poor.

single-phase

Specially designed for short-circuit impedance testing of single-phase transformers. Connect only one voltage output and a single-phase connection on the primary side. Select the "single-phase" mode in the parameter settings, and the calculation formula will automatically switch to a single-phase formula.

Filling in winding form (star/corner connection): The "winding form" in the parameter settings is filled in as the winding form on the wiring side (usually the high voltage side), which is independent of the secondary side short-circuit method. Correct filling is necessary to ensure that the Uk% calculation formula is applicable correctly.