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1. Application background

Different fans are often used in different industries, generally have external rotor fan, centrifugal fan, etc. For example, used in tells the tunnel, factory workshop, cars, 5G communication base station and so on. Different application environments have different effects on the fan, and the working conditions required for the fan are also different. When the ambient temperature is too high, or the fan operation heating is abnormal, it is easy to burn the motor and cause fire hazard. If the fan has a built-in heat protector, it can effectively avoid similar situations to ensure safety.

2. Protection principle

When the fan is running abnormally overheated or the ambient temperature is too high, and the temperature of the protector reaches the rated action temperature, the bimetallic sheet of the protector will deform, separate from the contact point, form an open circuit, and actively cut off the power supply. If the protector is in the control loop, it will transmit the signal to the motor control board and cut off the power supply. When the temperature returns to the normal state, the protector is reset again, and the fan works normally.

3. Installation site

  • Buried in the coil, connected with the main loop, so that the temperature is more accurate and sensitive, can directly cut off the power supply.

  • Attach the protector to the surface of the coil and wrap it with insulating tape.

4. lectotype

  • Volume: For embedding in the coil, circular ST01 and ST06 series. If placed on the coil surface, then select ST07, BW-B, etc.

  • Current: select ST01(6.3A) or ST06 or STH6(13.5A) according to the blocking and rated current of the fan (10A).

  • Temperature: generally 130℃, 150℃, 155℃ etc., 180C; most insulation level is F, and the higher requirements are H.

  • Contact switch form: generally open or closed, in addition to manual reset, only after power troubleshooting can be reset, to ensure the safety of maintenance personnel.

5. Precautions for use

  • Plastic pressure: pay attention to the plastic pressure should not be too large when the embedded coil is installed, and the metal shell under the pressure of the thermal protector should not exceed 30 KG, otherwise the metal shell of the protector will be deformed or broken, destroying the internal structure of the protector and affecting the product performance.

  • Blocking current: the blocking current of the fan should not exceed the maximum current of the protector, otherwise it will affect the life or burn the protector.

  • Vacuum immersion paint: If the motor involves the vacuum immersion paint process, attention should be paid to the vacuum degree, temperature and time of the process flow to ensure that it is within the range. Our products bear a maximum negative pressure of-0.09 Mpa.

  • Certification: UL, VDE / TUV, CQC, etc.


Want to discuss customization options, pricing, availability or other details? Click “Contact Us.”

Sales:Don Qu

Phone:+86 183 5813 1344

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