Calibration method of megohmmeter:

1. Impedance bridge with 1% accuracy in the range of 103 to 1012. High-precision relative humidity meter, high-precision thermometer.

2. Open the meter cover and be careful not to damage the two wires connecting the power switch on the circuit board.

3. Find the three calibration regulators at the bottom right of the circuit board.

4. Keep the megger under this environmental condition for at least 1/2 hour, and then start the test after obtaining self-balance.

5. Use the cable that comes with the ACL-800 watch to connect one end to the alligator clip and the other end to the banana plug.

6. Insert the 3.5 mm long plug into the socket of the meter.

7. Connect both ends of the resistor with alligator clips.

8. Three calibration regulators, the top one is "humidity" measurement, the middle one is "impedance", and the bottom one is "temperature adjustment with a small screwdriver". The clockwise direction is for increasing value adjustment, and the counterclockwise direction is for decreasing value adjustment.

9. Press the power switch of the megohmmeter and compare the values of "temperature", "humidity" and "resistance" at the same time.

10. Release the power switch, and slowly adjust the corresponding calibration regulator.

11. Press the power switch again and observe the LCD display.

12. If you need to re-calibrate, you can press the power switch again and adjust the calibrator.

13. Cover the meter cover and tighten the four fixing screws.

14. Press the power switch to confirm whether the watch is working properly.