I. Inspection and measures taken by the flow measurement and the actual value
4.1 Fault Reasons
1 The converter setting value is incorrect.
2 Sensor installation location is inappropriate, not full of tubes or liquids contain bubbles.
3. The cable insulation decreases during the signal cable or in the process of using.
4 the upstream flow condition of the sensor does not meet the requirements.
5 The sensor electrode changes in the resistance or the insulation of electrodes decreased.
4.2 Fault inspection and taking measures
1 Review the converter set value and check zero point, full value. First check whether the number of matched sensors and converters is checked. Most of the current sewage flowmeter in the manufacturer's real-flow calibration after the sensor brand (or with the table attached to the "manual") marked the calibration of instrumentation constants, and in the matching converter set up. Therefore, before debugging the new instrumentation to review the instrument constants, sensor number and converter number is paired. Because of this kind of mismatch incidents, also need to review the caliber, range and measurement units and other set values.
2 Check the condition of the piping liquid and whether it contains bubbles.
This kind of malfunction is mainly caused by the improper design of pipe network or the imperfect related equipments, can refer to the content of the pipeline not filled with liquid or liquid containing a little bubble.
3 Check the signal cable system;
Is it appropriate to check the connection cable matching? Is the connection correct? Does insulation fall?
Usually people inspect the sewage flowmeter to measure the flow of failure reasons, often ignore the connection between the sensor and converter cable system, often encountered the following examples:
(a) The attached whole cable is severed and reconnected after the use of a phase of the connection at the suction moisture, insulation drops;
b The signal line end is not handled well, the inner shielding layer, the outer shielding layer and the signal core have short connection between each other, or with the casing short;
c do not require the model (or attached) cables;
(d) The length of the cable exceeds the limit of the length of the liquid conductivity;
E The liquid conductivity is low and the sensors and converters are farther apart