As the core instrument of industrial process control, the stability of intelligent temperature transmitters directly affects production safety and product quality. However, in practical applications, devices may experience output abnormalities due to sensor failures, power interference, environmental factors, and other factors. This article combinesEB213The technical characteristics of intelligent temperature transmitters, the system identifies common types of faults, and proposes targeted maintenance plans.

1、 Typical fault classification and diagnosis

（1） Sensor related faults

Open circuit fault

When the thermistor/When the thermocouple circuit is disconnected, the output current of the transmitter will be fixed at the fuse alarm value (such as3.75mA）At the same time, the indicator light flashes. The open circuit position can be confirmed by measuring the sensor resistance or millivolt value with a multimeter, and replacing the probe or repairing the wiring can solve the problem.

short-circuit fault

A short circuit in the sensor can cause abnormal fluctuations in the output value or exceed the range (such as displaying garbled text). This fault is usually caused by insulation damage to the circuit or internal breakdown of the sensor. It is necessary to check the integrity of the cable shielding layer and replace the damaged sensor.

Virtual interruption and virtual shortening

This type of malfunction manifests as intermittent output abnormalities, often caused by sensor packaging defects or poor contact. It can be treated by tightening the wiring terminals, cleaning the oxide layer, or replacing the sensor module.

（2） Power system malfunction

Abnormal power supply voltage

EB213The power supply range of the intelligent temperature transmitter is12-40VDCIf the voltage is lower than9VDCMay cause unstable output, exceeding32VDCIt will permanently damage the equipment. A regulated power supply and an overvoltage protection device need to be installed.

Interference from shared power supply

When multiple devices share a power supply, starting and stopping high-power devices may cause voltage fluctuations or surges. It is recommended to use an independent power supply or install isolation transformers and surge suppressors.

（3） Environmental and installation issues

Severe temperature fluctuations

Long term exposure of equipment to high temperatures（>85℃）Or low temperature（<-40℃）In the environment, it may cause performance degradation of electronic components. Ensure that the installation location is away from heat sources and install insulation sleeves.

Mechanical vibration impact

Vibration may cause internal components to loosen or wiring to detach, leading to output jump. When installing, choose a vibration free area or use shock-absorbing brackets to fix the equipment.

Electromagnetic interference（EMI）

The electromagnetic fields generated by devices such as frequency converters and motors may couple to signal lines. Shielded cables (such as twisted pair cables) should be used, and single point grounding (grounding resistance) should be ensured<1Ω）.

2、 Systematic maintenance plan

（1） Daily inspection points

Appearance and wiring inspection

Clean the surface dust of the equipment every month and check whether the wiring terminals are loose or corroded. Using an infrared thermometer to monitor the operating temperature of the equipment, abnormal temperature rise may indicate internal faults.

Output signal verification

Simulate input through a standard signal generator and observe whether the output current is stable at4-20mAWithin the scope. If the deviation exceeds±0.1%FSCalibration is required.

（2） Regular calibration process

Equipped with sensor calibration

Insert the sensing part of the transmitter into a standard temperature source (such as a thermostatic bath), gradually change the temperature input, and calibrate the output current. for example, in0℃The100℃Verify linearity at key points.

Without sensor calibration

After disconnecting the sensor, use a standard resistance box to simulate the resistance value of a thermal resistor (such asPt100In0℃When is100Ω）Adjust the zero point and range of the transmitter to ensure that the output is consistent with the theoretical value.

（3） Emergency handling of faults

Output jump troubleshooting

step1Disconnect the sensor and simulate the input with a signal generator. If the output is stable, the fault is at the sensor end.

step2Check if the cable shielding layer is broken, replace the shielding cable or install a signal isolator.

step3Monitor power supply voltage fluctuations and useUPSOr filter to suppress interference.

Self diagnostic function utilization

EB213Intelligent temperature transmitter supports throughHARTThe handheld device reads the fault code. For example, when displaying“Err-03”When the sensor is disconnected, it indicates that the wiring needs to be checked immediately.

3、 Preventive maintenance recommendations

Environmental control

The installation location should avoid steam pipelines and areas with strong electromagnetic fields, and ensure good ventilation. For outdoor equipment, rain covers need to be installed.

Spare Parts Management

Reserve commonly used sensors, wiring terminals, and other vulnerable parts to shorten the time for fault repair.

personnel training

Regularly organize maintenance personnel to learn about equipment principles and fault phenomena, and improve the efficiency of problem localization.

The reliable operation of intelligent temperature transmitters depends on sensor quality, power stability, and environmental adaptability. By implementing a systematic maintenance plan, the failure rate can be significantly reduced and the equipment lifespan can be extended. It is recommended to develop a maintenance schedule based on the actual situation of the enterprise, such as conducting sensor calibration once every quarter and conducting a comprehensive inspection of the grounding system every year, in order to build a highly available temperature monitoring network.