How to deal with daily conductivity meter problems

(1) Power supply

1. When the conductivity meter is powered by a low voltage AC power supply, the indicator light and each filament are off. You can first check if the power input, transformer primary, transformer secondary low voltage, etc. are normal.

2. The LED and each filament may light under the high voltage DC power supply, but the electric eye tube does not emit green light, and if it is invalid to replace the new electric eye tube, you can check the high voltage DC power supply part first (you can use the AC 500V voltmeter file. Measure the voltage of the two anodes of the rectifier tube). Check secondary high voltage or transformer wiring. If there is electricity, measure the cathode of the rectifier with a DC voltage of 500 V, and it should be about +200 V or more with respect to ground. If there is no voltageDC or low voltage, replace rectifier tube or filter capacitor. And connect all contacts.

(2) Oscillator and cathode output device failure

When the conductivity meter cannot measure the exact balance point with the high-cycle gear, you can first replace the oscillator tube and the cathode output tube, if the problem cannot be solved, it is necessary to measure the voltage and the wiring of each pole of the two tubes. The anode of the oscillation tube should be about ten 150V, and the second grid is about +60V. The anode of the CRT output tube should be about +250V. You can use high impedance headphones or speakers, or you can use an oscilloscope to track and verify each point in the signal. This way you can spot the problem.

(3)Problems with the bridge part of the conductivity meter

When the high cycle gearé or low-cycle gear rotates the reading knob or magnification knob during measurement, the indicator flashes unsteadily. Or just can\'t find the balance.

1. First check the electrode system in the bridge

Remove the electrode and connect it to a known resistance of approximately 1000 ohms. If you can measure the resistance of around 1000 ohms, the problem will be solved on the electrodes or the wiring. Replace or repair the electrode system. If it cannot be measured, the following method can be used to continue the check.

2. The play button part

Sometimes the resistance of the sliding wire inside the play button is not in good contact. You can use a clean silk cloth to wipe the contact points to make good contact everywhere.

3. The magnification button part

Mainly due to the dislocation of the magnification switchinner strip or poor contact, you can use cotton to absorb a small amount of absolute ethanol or trichloroethylene to wipe off and reset.

4. Capacity problem

Sometimes the edge of the conductivity meter indicator light strip is blurred, and the capacity of the bridge arm can be adjusted to determine the clarity.

(4) Indicator failure

1. If the edge of indicator light strip is still blurred after the conductivity meter adjusts the capacitance of the bridge circuit, you can replace the 6E1 or 6E2 electric eye tube, the green fluorescent strip of the first moves in a fan shape, while the second moves up and down, and the wiring is different.

2. The indicator is not sensitive. At this point, you can replace the amplifier tube and electric eye tube. If still not sensitive, you need to check the voltage and wiring of each pole.

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