ST01 Series


Key Benefits:
• First China-made round shape thermal protector got UL,TUV and CQC certifications and broke 30 years’ monopoly of Germany protectors.
• Good sealed, can prevent product failure from vacuum impregnation process.
• Small size, suitable to be embedded inside coil.
• Metal case, up to 50KG coil shaping pressure, has high thermal conductivity and temperature sensitive.
• Pure temperature action type products, bimetal-disc without current and heat effect, accurate temperature control.




• Motors
• Transformers
• Coils
• Electronics, sensor


Integration of Resources:

• Integration of global supply chain resources, we purchase bimetal-disc from the world’s largest bimetal-disc material manufacturer EMS in the Unitd States and case from German supplier who uses stamping forming technology.
• Spring which material comes from NGK Japan and manufactured by Japanese stamping supplier.
• Silver plating technology on case and spring which greatly reduces the contact resistance.
• The key component bimetal-disc produced by fully automated molding equipment and sorted by tunnel oven separation equipment is good consistency and stable performance.


Technical Data

  Normally closed/Normally open
Nominal switching temperature, in 5K-step(TK) 60~180℃
Tolerance-Standard ±5K/±8K/±10K
Reset temperature range -30K±15K
Max.operating voltage 500VAC/60VDC
Working current 250VAC, 6A
Cycles at 250VAC/3.0A cosφ1.0 10000
Cycles at 250VAC/6.3A cosφ1.0 3000/N
Cycles at 250VAC/4.0A cosφ0.45 1000/N
Cycles at 250VAC/1.0A cosφ0.45 10000/N
Contact resistance(lead length 55mm) <50mΩ/N
Insulation voltage 1.5KV
Insulation sleeve length “a” >15mm
Diameter “d” <8.9mm
Height “h” <4.6mm
Lead wire-electric UL3398 AWG22 300V 150℃
Lead wire-teflon UL10362 AWG22 600V 250℃
Lead wire-silicone UL3135 AWG24 600V 200℃
Outgoing line length-standard L1=L4=520±10mm


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