The zinc oxide arrester tester is the equipment for the field test* of the power system and the zinc oxide arrester production plant. The following explains its usage and troubleshooting analysis:

How to use the instrument

1.Open the cover of the instrument box and firmly ground the instrument shell.

2. Insert one end of the arrester into the high-voltage bushing (H end) of the instrument, and clamp the other end to the L end (red terminal) with a wire clamp. Or use an insulated wire to lead out the external test sample from the high voltage end. Note: L end For measuring ground, it is forbidden to connect with the protective ground wire (earth).

3.Turn on the power switch. After the internal self-test of the instrument, the alarm light is on and the discharge light is on. After pressing the detection button, the indication value of the two meters is zero ± 1 word.

4. Press the reset button once, the alarm light is off, the instrument enters the detection state, the calibration/measurement switch button is placed in the measurement state (when it is raised), and the test can be performed.

5. Press the detection button for about 1 second and release it, and the instrument automatically completes all the detection items of the MOA. The voltage under U1mA and the leakage current under 0.75U1mA are displayed separately and automatically locked on the two meters.

 6. Matters needing attention

(1) If the alarm light is on when the detection button is pressed, it indicates that there is a defect in the internal contact of the MOA, or the external wiring is not strong, after the discharge lamp is on, check whether there is a problem with the external wiring, or press reset after replacing the test product. Key to proceed to the next test.

(2) If the alarm lamp does not light up, it indicates that the internal contact of the MOA is good and there is no problem with the wiring. , Remove the test wiring or replace the test product for the next test.

Instrument debugging and troubleshooting

 1. Zero adjustment of the meter head

 After the instrument has been used for a period of time, it may need to be adjusted. The adjustment method is: start the instrument, the alarm light is on, (do not connect the test product at this time), press and hold the detection button, adjust the corresponding potentiometer on the panel, until the meter The head instructions are "zero ± 1 word". The voltage and current zero adjustments are carried out separately.

 2. 0.75U1mA calibration

 Set the calibration/measurement switch button to 0.75U1mA state (when pressed), connect the test product, press the test button, and read the voltage value of U1mA, then release the test button, and the instrument voltage will immediately change to another voltage. The value U1 is 0.75U1mA, and the two are compared and calibrated. If U1=0.75U1mA, no adjustment is required; U1≠0.75U1mA, then make appropriate adjustments and adjust the corresponding potentiometer on the circuit board until U1=0.75U1mA. After calibration, the measurement accuracy can be guaranteed for a long time without frequent adjustments. After the calibration is completed, set the calibration button to U1mA state.

3. Instrument error adjustment

After the instrument has been used for a period of time, if an error is found, it can be adjusted. Connect a test product with a known U1mA, assuming it is 27.0kV. Press and hold the detection button to see if the indicated value of the voltmeter is consistent with the reference voltage of the test product. U1mA (27.0kV) is equal.

4. Handling of simple faults

If the head of the ammeter displays "[[[" or the sum is not adjusted to zero, it means that the input protection level op amp (CA3140E) IC1 of the current loop is equivalent to the fuse is damaged. Replace the configured components. If it is a voltmeter, replace IC2.