Our operators should accumulate some equipment troubleshooting and handling skills in their daily operations, so that they will not be at a loss in case of emergencies. Here are our tips for dealing with overheating alarms in walk-in high-temperature aging rooms, which we hope to learn from.
1. Check if the AU1 indicator light of the over temperature protector is lit. If it is lit, it indicates that the temperature inside the box exceeds the upper limit alarm value (HIAL) or lower limit alarm value (DIAL). Then check if the set value is correct (10 degrees below the temperature control temperature). If the set value is incorrect, modify the set value. If the set value is correct, it may be caused by the following reasons:
① The test box fan does not rotate or is in a solid staterelayBreakdown, the heating tube keeps heating, causing overheating;
②sensorDamage;
③ The temperature limiter itself is damaged;
2. Check if the temperature sensor is damaged. First, remove the three wires (A+, B+, B -) of the sensor and measure the resistance with a meter. When measuring a good sensor, two of the wires (B+, B -) should be connected, and the resistance of either wire (A+) or the other two wires (B+, B -) should be around 110 Ω. Otherwise, it proves that the sensor is damaged and can be replaced (if it isthermocoupleMeasure whether the two wires are connected when the input is received.
3. Check if the solid-state relay is damaged. If it is not powered on, use a meter to measure if the input and output terminals are conductive. If it is conductive, it indicates solid-state breakdown. Otherwise, if it is non-conductive, observe if the conductivity indicator light on the solid-state relay is on. If it is on, use the voltage range of the multimeter to measure if the output terminal (pin 1) of the solid-state relay has a 220V voltage on the N line. If not, check the contactor again. If there is, measure if the output terminal (pin 2) of the solid-state relay has a 220V voltage on the N line. If not, it indicates that the solid-state relay is internally open and damaged and needs to be replaced.
4. Check if the fan is rotating, the detection method is as follows:
(1) Place the machine in operation, open the box door, and observe whether the air drum is running; If the wind drum does not rotate, it may be due to the wind drum andmotorThe shaft is stuck, cut off the power, open the louver frame and manually rotate the air drum to test if it improves. Please carefully observe whether there are any obstacles around it, and remove them if there are.
(2) Exclude the above situation and check if the motor is damaged. Measure the resistance at both ends of the axial current motor circuit with a multimeter. If the resistance of a normal axial current motor is within the range shown in the figure below, it is considered normal. Otherwise, it indicates that the motor is damaged and can be replaced.