1. This instrument can only be used on equipment that is de-energized; the grounding terminal should be reliably connected to the grounding grid,
and the instrument should be used in a spacious, safe, and reliable location as much as possible.
2. The equipment under test must be disconnected from the high-voltage leads and switched from operational status to maintenance status, cleaned, and after preliminary insulation tests are satisfactory, the instrument can be used for testing to prevent damage to the instrument during voltage application due to poor insulation of the equipment under test.
3. Determine the appropriate wiring method based on the installation situation of the equipment, and select the corresponding wiring method in the relevant menu options.
4. Correctly select the test voltage level according to different equipment, and choose the required voltage in the corresponding menu options.
5. In case of special situations that endanger safety during testing, the main power can be urgently turned off.
6. Only after disconnecting the power switch on the panel and clearly disconnecting the 220V test power supply can wiring changes be made or work be concluded; when repeating tests on the same test equipment, press reset and then re-measure, or choose to repeat after the previous test is completed.
7. To ensure measurement accuracy, especially when the loss of small capacitance test samples is small, it is necessary to ensure that the low-voltage terminal (or secondary terminal) of the equipment under test has good insulation and measure in an environment with relatively low humidity.
8. When conducting tests on large capacitance test samples, the grounding of the instrument and the grounding of the test sample should not be at the same grounding point to prevent back-surge voltage or traveling waves from affecting the safety of the instrument during grounding discharge.
9. The instrument comes with a voltage boosting device; attention should be paid to the insulation distance of the high-voltage leads and personnel safety; 10. The instrument should be reliably grounded; poor grounding may cause machine protection or danger.
10. After the instrument is started, except for special circumstances, it is not allowed to suddenly cut off the power to avoid overvoltage damage to the equipment;
11. Although the special high-voltage wire (HVx) provided with the instrument has passed factory inspection, it should still be kept away from the human body and the low-voltage test wire (Cx) during measurement; neither the high-voltage core wire nor the high-voltage shield wire is allowed to be grounded or connected to the low-potential part of the test circuit.
The core wire and shield wire of the CX input line are not allowed to contact the high-voltage part of the test circuit.
12. The instrument should be protected from moisture and severe vibration.
13. When on-site interference is significant and reliable results cannot be obtained with power frequency, heterodyne frequency measurement should be used; in other cases, power frequency measurement should be used.
14. If after issuing a measurement command, the measurement result does not appear on the screen for a long time (1 minute), it may be due to the test sample capacitance being too large or a system crash; restart the instrument and lower the measurement voltage before measuring again.
15. A short circuit in the test sample will prevent measurement, and the instrument will automatically protect itself. When a section of paper protrudes from the paper outlet at the top of the machine, press the button once to stop paper feeding. The printing paper is allowed to be pulled outward.
Instrument Structure
Measurement Circuit: All calculations such as Fourier transform, complex number operations, range switching, and variable frequency power supply control.
Control Panel: Printer, keyboard, display, and communication relay.
Variable Frequency Power Supply: Uses SPWM switching circuit to produce high-power sine wave regulated output.
Step-up Transformer: Boosts the variable frequency power supply output to the measurement voltage, with maximum reactive power output of 2KVA/1 minute.
Standard Capacitor: Internal Cn, measurement reference.
Cn Current Detection: Used to detect the current of the internal standard capacitor, 10μA～1A. Input resistance <2Ω.
Cx Positive Wiring Current Detection: Only used for positive wiring measurement, 10μA～1A. Input resistance <2Ω.
Cx Reverse Wiring Current Detection: Only used for reverse wiring measurement, 10μA～1A. Input resistance <2Ω.
Reverse Wiring Digital Isolation Communication: Uses precision MPPM digital modulation and demodulation to transmit the reverse wiring current signal.
