What are the operating specifications and safety precautions for lightning protection component testers?

1. Preparation before testing (3 items must be done)

Instrument inspection:

The appearance is undamaged, the power cord and test probe (high-voltage probe) are intact, and the grounding terminal is firmly connected (grounding resistance ≤ 4 Ω).

Power on self-test, confirm that the display screen, buttons, and indicator lights are normal, and the calibration certificate is valid (at least once a year).

Check that there is no short circuit in the test circuit, there is no oil/oxidation on the high-voltage output terminal, and the insulation layer of the probe is not cracked.

Environment and personnel preparation:

Environmental requirements: temperature between 10-35 ℃, humidity ≤ 70%, no flammable or explosive materials, and an insulated pad (withstand voltage ≥ 10kV) should be laid on the operating table.

Personnel protection: Wear insulated gloves (withstand voltage ≥ 5kV), insulated shoes, goggles, and metal jewelry (such as watches and necklaces) is prohibited.

Processing of the tested item:

After the lightning protection components (varistors, discharge tubes, etc.) are powered off, discharge them (capacitors should be left to stand for more than 5 minutes), and clean the oxide layer on the pins.

Clearly define the component specifications (such as rated voltage and current capacity), and determine the test parameters in accordance with the national standard (GB/T 18802) or component manual.

2. Parameter setting and wiring (core steps)

Parameter setting:

Select test type: Select according to the tested component (such as "varistor" or "discharge tube"), and specify the test mode (breakdown voltage/leakage current/current carrying capacity).

Set key parameters: voltage range (such as selecting 0-5kV DC for varistors), leakage current threshold (such as ≤ 10 μ A), testing time (1-10s), impulse current type (8/20 μ s, used for current capacity testing).

Confirm protection parameters: Enable overcurrent protection and high-voltage short-circuit protection, and set the protection current (usually 1.2 times the test current).

Wiring specifications for lightning protection component tester:

Wiring sequence: Connect the tested object first, then connect the instrument testing terminal. Connect the red probe to the positive terminal (or input terminal) of the component, and the black probe to the negative terminal (or ground terminal). It is strictly prohibited to connect it in reverse (especially during high-voltage testing).

Current capacity test: Use specialized high current wires and tighten the wiring terminals to avoid poor contact and arc generation.

No no-load wiring: The tested object must be connected first, and then the high-voltage output must be turned on to prevent no-load voltage boosting.

3. Testing process operation (execution in different modes)

Conventional parameter testing (breakdown voltage/leakage current):

Start test: Press the "Start" button and observe the voltage slowly rising (rapid boost is prohibited), and monitor the leakage current and breakdown voltage data displayed by the instrument in real time.

Data recording: If the test value is within the rated range of the component (such as V1mA ± 10% for varistors), it is judged as qualified and the data is recorded; If the leakage current exceeds the standard or the breakdown voltage is abnormal, immediately press the "emergency stop" button.

Current capacity test (impulse current mode):

Confirm that the test circuit is securely connected and that unrelated personnel are kept away from the testing area (radius ≥ 1.5m).

Start the impact test, observe whether the instrument displays "impact successful", record data such as residual voltage and current flow time, and wait for the instrument to discharge automatically (≥ 30 seconds) after the test.

Batch testing attention:

After testing 10 components, pause for 5 minutes to avoid overheating of the instrument; When replacing components, the high-voltage output must be turned off first before disconnecting and wiring.

4. Conclusion after testing (3-step safety process)

Turn off high voltage output: Press the "stop" button and wait for the instrument voltage to drop to 0V (the display screen shows "discharge completed").

Safe wire removal: First remove the testing end of the instrument, then remove the tested object, and discharge the tested object again (especially after current capacity testing).

Instruments and Data Processing:

Turn off the power, clean the test probe and instrument surface, and store them in a dry and ventilated place.

Organize test reports, record qualified/unqualified situations, abnormal data (such as breakdown voltage offset), and archive and retain them.

2、 Safety precautions (red line clause)

1. Personnel safety（Prohibited)

It is strictly prohibited to operate without a license. Operators must undergo professional training and be familiar with the instrument manual and lightning protection testing standards.

When conducting high voltage testing (≥ 5kV), it must be operated by a single person and monitored by a dedicated person. The emergency stop button is easily accessible, and touching the test probe, tested product pin, and high voltage output terminal is prohibited.

If electric shock occurs, immediately cut off the main power supply, use insulated tools (such as dry wooden sticks) to detach from the contact power source, and prohibit direct contact with the injured person.

If there is an arc, abnormal noise, or smoke during the testing process, immediately press the "emergency stop" button, turn off the power, wait for 10 minutes before checking, and do not open the cover for repair on the spot.

2. Instrument safety (avoid damage)

Overlimit testing is strictly prohibited: using a 10kV instrument to test discharge tubes with a rated voltage of 20kV, or using a 1kA instrument to test components with a current capacity of 5kA, may cause the high-voltage module of the instrument to burn out.

Prohibit no-load boosting: When the tested object is not connected, do not turn on the high-voltage output, otherwise it will damage the internal high-voltage generator of the instrument.

Current capacity test: After a single test, the interval should be ≥ 30 seconds to avoid continuous impact causing the instrument to overheat; During high current testing, the cross-sectional area of the wire should be ≥ 4mm ² to prevent the wire from heating up and catching fire.

Instrument malfunction handling: In case of voltage loss of control, abnormal display, or unresponsive alarm, immediately cut off the power and contact the original factory for repair (such as Shanghai Sanji Electronics and Nanjing Changsheng after-sales). Disassembly by oneself is prohibited.

3. Environment and safety of the tested object

Set up a "high voltage danger" warning sign in the testing area, prohibiting unrelated personnel from entering, especially during impulse current testing (instantaneous high current may cause arcing).

Prohibited from use in damp, dusty, and corrosive gas environments. Temporary protective shelters should be built for outdoor testing to avoid rainwater splashing on the instruments.

If the tested object is damaged (such as explosion or leakage), testing is prohibited to prevent short circuits or debris splashing during testing.