Common issues with PH meters and how to fix them
1. Turn on the power, the indicator light is off
(1) If the acidity meter has voltage output, check whether the indicator light is burnt out;
(2) If the acidity meter has no voltage output, check whether the fuse ALL is new;
(3) If the fuse is not blown, check whether the transformer of the instrument is burned out due to a partial short circuit in the circuit.
2. When the power is turned on, the indicator on the meter head of the instrument is unstable or the pointer is not positioned
(1) Open the panel of the acidity meter to check whether the meter head is stuck, and observe whether there is any foreign matter on the coil;
(2) Check whether the instrument case is grounded.
3. When the power is not turned on, the indicator of the meter head swings sharply; open the panel of the instrument to check whether the parallel resistance welding at the input end behind the meter head is firm.
4. After the digital acidity meter is powered on, the displayed number is unstable or drifts
(1) Check whether the connectors of the acidity meter are firm;
(2) Check whether the input and output voltage of the instrument are stable;
(3) Check whether the circuit board of the instrument is corroded;
(4) Check whether the operational amplifier in the amplifier circuit of the instrument is burnt out.
5. The output indication of the acidity meter is inaccurate; the detection method is incorrect or the temperature and slope adjustment points are incorrect.
6. The two standard solutions cannot be used for mutual positioning; check whether the standard signal generator is inaccurate.
7. The acidity meter can work normally when it is directly input, but the indication value is out of tolerance when it is connected in series with high resistance.
(1) Check whether the filter capacitor of the instrument is broken down;
(2) Check whether the input resistance of the field effect bamboo of the instrument is low;
(3) Check whether the circuit board of the instrument is damp or corroded.
8. After the digital acidity meter is powered on, the numbers displayed are missing strokes
(1) The connector of the instrument is not in good contact;
(2) The digital display of the acidity meter is damaged.
9. The temperature, slope or correction adjustment knob on the acidity meter panel is out of order; check whether the potentiometer connected to the out-of-function knob is damaged
