The transformer DC resistance tester uses a 32-bit ARM core as the processing core to control the whole machine and automatically complete functions such as self-calibration, current stabilization judgment, data processing, and resistance display. It can measure the DC resistance of various types of transformers and instrument transformers.
Operating instructions for a transformer DC resistance tester:
1. The instrument offers the following testing options: simultaneous three-phase testing of YN windings, phase-by-phase testing of YN windings, magnetization method testing of low-voltage windings in five-limb low-voltage angle-connected transformers, phase selection testing of low-voltage windings in three-limb low-voltage angle-connected transformers, and the ordinary four-terminal method.
2. Use the mode key to select different test modes to test the current.
3. The instrument repeatedly tests the current and potential. The LCD screen displays the resistance value of the repeated test. If the repeated test results are consistent, it means that the instrument is working normally. If the test value has a large error compared with the factory value, the wiring should be checked to see if it is correct.
4. After the test is completed, press the reset button to disconnect the charging circuit. The instrument has an internal fast discharge circuit to release the energy stored in the windings. After pressing the reset button, the buzzer sounds, indicating that the instrument is in discharge mode. The clock starts the discharge timing, and the LCD screen displays various discharge voltage values. The buzzer stops, indicating that the discharge is complete. The LCD screen will then display the measured data again. At this point, you can remove the test leads or reselect the current, test method, and tap position to perform the test. You can also use the → and ← buttons to view the measured data for each tap.
Precautions for using a transformer DC resistance tester:
1. For no-load tap changing windings, switching is not permitted during energization.
2. Test leads must not be removed during the power-on process.
3. If the external AC220V power suddenly fails during testing, the test leads can only be removed after five minutes.
4. For medium and low voltage star windings, three-phase simultaneous testing is not applicable.
5. If there is no display after powering on, check the AC220V power supply wiring.
6. Check if the internal components of the instrument are loose.
