| NO. | Fault | Reason | Treatment |
| 1 | No outputs |
Is the switch of the pressure guide tube not turned on | Open pressure guide tube |
| Whether the guide pressure pipeline is blocked | Unclogging of pressure-guide tubes | ||
| Is the power supply voltage too low | Adjust the supply voltage to 24V | ||
| Is there any disconnection in the output circuit of the transmitter | Turn on the breakpoint | ||
| Is the power supply connected incorrectly? | Check power supply, correct wiring | ||
| Poor contact with the internal connector | lookup processing | ||
| If with a transmitter head, the transmitter head is damaged | Change the transmitter head | ||
| Electric equipment failure | Replace the board with a new one or look for faults according to the transmitter’s operating instructions |
||
| 2 | Excessive output |
Residual liquids and gases in the pressure-guide tube | Discharge of liquids and gases from the pressure-guide tube |
| Output wires are reversed or connected incorrectly | Inspection and processing | ||
| Jamming of the main or auxiliary lever or detection plate, etc. | Inspection and processing | ||
| Poor internal connector contact | Inspection and processing | ||
| Electric equipment failure | Replace the board with a new one or look for faults according to the meter’s operating instructions |
||
| Damaged pressure sensor | Change pressure sensor | ||
| Whether the actual pressure exceeds the selected range of the pressure transmitter |
Re-select pressure transmitter with appropriate range | ||
| 3 | Output too small |
The transmitter power supply is normal or not | If it is less than 12VDC, check whether there is a large load in the circuit, the input impedance of the transmitter load should be by RL ≤ (transmitter supply voltage – 12V)/(0.02A) Ω |
| 4 | Unstable output |
Whether the actual pressure exceeds the selected range of the pressure transmitter |
Re-select pressure transmitter with appropriate range |
| Whether the pressure sensor is damaged (severe overloads can sometimes damage the isolation diaphragm) |
Need to be sent back to the manufacturer for repair | ||
| Residual liquids and gases in the pressure-guide tube | Discharge of liquids and gases from the pressure-guide tube | ||
| Influence of pulsations in the measured medium | Adjust damping to eliminate effects | ||
| Supply voltage too low or too high | Adjust supply voltage to 24V | ||
| Poor contact or intermittent short circuit in the output circuit. | Inspection processing | ||
| Loose wiring, wrong power cord | Check wiring | ||
| Multiple ground points in the circuit | Check that the treatment retains a point of grounding | ||
| Poor internal connector contact | Inspection processing | ||
| Damaged pressure sensor | Replacement of the transmitter | ||
| 5 | Incorrect pressure indication |
The transmitter power supply is normal or not | If it is less than 12VDC, check whether there is a large load in the circuit, the input impedance of the transmitter load should be by RL ≤ (transmitter supply voltage – 12V)/(0.02A) Ω |
| Is the reference pressure always correct? | If the accuracy of the reference pressure gauge is low, it must be replaced with a more accurate gauge. | ||
| Whether the range of the pressure-indicating instrument is the same as the range of the pressure transmitter |
The range of the pressure-indicating instrument must be the same as the range of the pressure transmitter. |
||
| Correct wiring of the input and corresponding wiring of the pressure indicator gauge |
Pressure indicating instrument input is 4 ~ 20mA, the transmitter output signal can be directly accessed; if the pressure indicating instrument input is 1 ~ 5V must be the pressure indicating instrument input and connected to a precision of 1 ‰ and above, the resistance value of 250 Ω resistor, and then access to the input of the transmitter |
||
| The input impedance of the transmitter load shall be in accordance with ≤ (transmitter supply voltage – 12V)/(0.02A)Ω. |
If not, according to its different measures can be taken: such as increasing the supply voltage (but must be less than 36VDC), reducing the load, etc. |
||
| Whether the input is open when there is no recording in the multi-point paper recorder | If open-circuit, no other loads can be carried; change to other recorders with input impedance ≤ 250Ω when no recordings are made |
||
| Whether the corresponding equipment enclosure is grounded | Equipment enclosure grounding | ||
| Is it wired separately from AC power and other power sources? | Separate wiring from AC and other power sources | ||
| Whether the pressure sensor is damaged (severe overloads can sometimes damage the isolation diaphragm) |
Must be sent back to the manufacturer for repair | ||
| Whether there is sand, impurities, etc. in the pipeline to block the pipeline (the measurement accuracy will be affected by the presence of impurities) |
Must be cleaned of impurities, and add a filter before the pressure excuse |
||
| Whether the temperature of the pipeline is too high (the operating temperature of the pressure sensor is -25~85℃, but it is better to use it within -20~70℃ in practice) |
Add a buffer tube to dissipate heat, it is best to add some cold water to the buffer tube before use to prevent overheated steam from directly impacting the sensor, thereby damaging the sensor or reducing the service life. |