The correct usage method of the overheat protector (temperature switch) directly affects the protection effect and safety of the equipment. The following is a detailed installation, commissioning and maintenance guide:
I. Installation Method
1. Location selection
Direct contact with heat sources: Installed in areas prone to heat generation (such as motor windings, transformer coils, and the surface of heat sinks).
Avoid mechanical stress: Stay away from areas prone to vibration or pressure to prevent misoperation.
Environmental adaptation
Damp environment: Select waterproof models (such as the sealed type of ST22).
High-temperature environment: Heat-resistant casing (such as KLIXON 8CM can withstand a short-term high temperature of 200°C).
2. Fixed method
Bundled type: Fixed to cylindrical components (such as motor coils) with metal cable ties.
Embedded: Insert into the reserved slot of the device (such as the plastic-sealed slot of an electric water heater).
Screw fixation: Some high-current models need to be fastened with screws (such as 30A protectors).
3. Wiring specifications
In series in a circuit: Connected to the main circuit or control loop (such as the power line of a motor).
Polarity note: Some DC protectors need to distinguish between positive and negative poles (such as the 6AP1 series).
Wire specification: Match the load current (for example, a 10A load requires ≥1.5mm² wire).
Ii. Debugging and Testing
1. Action temperature verification
Use a constant-temperature heating source (such as a hot air gun) to slowly increase the temperature, and use a multimeter to check the on-off status.
Compare the nominal value (for example, the nominal value of KSD301 is 100°C±5°C) to confirm whether the actual operating temperature is within the tolerance range.
2. Reset function test
Self-reset type: It should automatically restore conduction after cooling (such as ST22).
Manual reset type: The reset button needs to be pressed (for example, 6AP1 needs to be triggered with an insulating rod).
3. Load testing
After power-on, simulate overload (such as motor blockage) and observe whether the protector cuts off the circuit in time.
Iii. Daily Maintenance
1. Regular inspection
Check whether the contacts are oxidized once a month (especially in high-humidity environments).
Check if the fasteners are loose (they tend to shift in a vibrating environment).
2. Troubleshooting
No action: It may be due to aging or sintering and needs to be replaced.
False action: Check whether the installation position is disturbed by external heat sources.
3. Change the standard
Exceeding the rated number of actions (such as 10,000 cycles).
The casing is deformed or the contact resistance is significantly increased (measured with a multimeter, it should normally be less than 0.1Ω).
Iv. Safety Precautions
1. It is strictly prohibited to use beyond the specified specifications
For example: protectors with a nominal voltage of 5A/250V cannot be used in 30A circuits.
2. Do not short-circuit the protector
Temporarily skipping protection may cause the equipment to burn out.
3. Special environmental protection
For chemical plants, anti-corrosion models (such as stainless steel enclosures) should be selected.
Note: There may be slight differences among different brands and models. Be sure to refer to the technical manual of the specific product. If it is used for critical equipment (such as medical or military), it is recommended to calibrate it regularly or adopt redundant protection design.
Post time: Aug-08-2025