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1. Application background

Thermal protector is also very widely used in the transformer industry, mainly ring transformer, large dry-type transformer, medical transformer and so on. When the ambient temperature is too high, or the transformer operation heat is abnormal, it is easy to burn down and cause fire hazard. If the built-in thermal protector can effectively avoid similar situations, to ensure safety.

2. Protection principle

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

3. Installation site

  • Buried in the coil and connected with the main loop, so that the temperature is more accurate and sensitive.

  • Place the protector on the surface of the coil and wrap it with insulation tape.

4. lectotype

  • Volume: For embedding in the coil, circular ST01 and ST06 series.

  • Current: select ST01(6.3A according to the rated current voltage) or ST06 (10A), etc.

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

5. Precautions for use

  • Plastic pressure: pay attention to the plastic pressure after the embedded coil should not be too large, the pressure of the metal shell 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.

  • Voltage current: the maximum current of the transformer should not exceed the maximum current of the protector, otherwise it will affect the life or burn the protector.

  • Soak paint: if it involves the dip paint process, attention should be paid to the process, whether it is dripping paint or immersion and whether to vacuum, and pay attention to the vacuum degree, temperature and time of the process to ensure that it is within the range. Our maximum negative pressure is-0.09 Mpa.

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


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Sales:Don Qu

Phone:+86 183 5813 1344

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