1、 Common types of faults and troubleshooting strategies

1. Abnormal temperature display: manifested as numerical jumps, no display, or significant deviation from actual values. Prioritize checking whether sensors (such as thermocouples, thermistors) are loose, aging, or have disconnected wiring; If the sensor is normal, it is necessary to check whether the temperature control meter parameter settings (such as division number and range) are incorrect, or if the instrument module itself is damaged.

2. Heating/cooling failure: If the temperature does not rise in heating mode, it may be due to heating tube burnout, contactor contact oxidation, or solid-state relay (SSR) failure; The cooling mode drops slowly, and it is necessary to check whether the circulation pump is stuck, the coolant pipeline is blocked, or the valve is not open.

3. Frequent over temperature alarms: In addition to sensor false alarms, improper PID parameter settings (such as narrow proportional bands) often cause system oscillations, or delayed response of actuators (such as regulating valves), making it difficult to adjust heat input in a timely manner.

4. System unresponsive: The main causes are power phase loss, fuse failure, or control circuit disconnection. The power supply line can be checked step by step with a multimeter to confirm the status of the circuit breaker and relay.

2、 Key maintenance techniques

1. Regular cleaning and calibration: Clean the surface of the sensor (especially the probe that comes into contact with the material) monthly to avoid temperature distortion; Compare the displayed values of the temperature control meter with a standard thermometer every quarter, and recalibrate if the deviation exceeds ± 0.5 ℃.

2. Lubrication and fastening: Add high-temperature lubricating grease to the moving parts such as the bearings of the circulation pump and the connecting rods of the contactor every six months; Tighten all electrical connectors (such as terminal blocks and sensor wiring) to prevent vibration loosening and poor contact.

3. Preventive replacement of vulnerable parts: Heating tubes, SSRs, and other components have a lifespan of about 1-2 years and can be replaced in advance according to their operating hours; The aging of the sealing gasket can easily lead to coolant leakage, and it is recommended to check it once a year.

4. Data recording and analysis: Export historical curves through the temperature control system backend, observe temperature fluctuation patterns, and if periodic anomalies occur (such as overheating every 8 hours), targeted troubleshooting of scheduled tasks or external interference sources can be carried out.