Thermocouple is a commonly used temperature sensor, but various faults may be encountered during use. The following are common causes of thermocouple failures and their solutions:
1. Causes and treatment methods of poor thermocouple contact failure
1. Loose terminals or poor contact: The solution is to check and tighten the terminals to ensure good contact.
2. The contact surface between the thermocouple and the object being measured is poor: the solution is to clean the contact surface to ensure good contact.
3. Broken wire: The treatment method is to check whether the wire is broken. If there is a break point, the wire needs to be replaced.
2. Causes and treatment methods of thermocouple circuit failures
1. Line short circuit: The solution is to check the line, find the short circuit point, and repair or replace the wire at the short circuit.
2. Open circuit: The solution is to check the circuit, find the open circuit point, and repair or replace the wire at the open circuit.
3. Reasons and solutions for slow or insensitive temperature response
1. There is an accumulation of impurities in the external protection tube: The solution is to clean the impurities in the external protection tube.
2. The external protective tube is damaged: The solution is to replace the external protective tube.
3. Temperature sensor aging: The solution is to replace the temperature sensor.
4. Causes and treatment methods of abnormal thermocouple output signal failures
1. The connecting cable is loose: The solution is to check and ensure that the connecting cable is tight.
2. External electromagnetic interference: The solution is to isolate the thermocouple from the interference source, such as using an electromagnetic shielding cover.
3. Instruments are damaged: The solution is to check the instruments and meters, and repair or replace them if they are damaged.
5. Causes and treatment methods of low thermocouple insulation resistance failure
1. Wire insulation damage: The treatment method is to check whether the wire insulation is damaged, and if it is damaged, repair or replace it.
2. Aging of wire insulation: The treatment method is to check whether the wire insulation is aging, and if so, repair or replace it.
6. Causes and treatment methods of thermocouple temperature drift failure
1. Ambient temperature changes: The solution is to perform temperature calibration under stable ambient temperature conditions to eliminate temperature drift.
2. Thermocouple aging: The solution is to replace the thermocouple.
7. Causes and treatment methods of thermocouple wire breakage
1. The wire is pulled too much: The solution is to check whether the wire is pulled too much, and if so, repair or replace the wire.
2. Aging of wires: The treatment method is to check whether the wires are aging, and if so, repair or replace the wires.