ST08 Thermal protector

Power class: 18 A to 27.5 A

Type series: ST08

normally closed

resets automatically

with pin

without insulation

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ST08 Thermal protector

ST08 is a protector with double protection function of overcurrent and overtheating, and its built-in heating wire and bimetal form a series circuit. The overload current when the motor is blocked will make the heating wire heat up rapidly, which will heat the bimetal disc and accelerate the heating speed of it, so that the bimetal disc can reach the rated operating temperature faster and bounce open, cutting off the circuit. The heating wire with different resistance values has different heat generation, resulting in different trip times. By adjusting the resistance of the heating wire, it is possible to control the tripping speed of the protector when the current value is fixed.

PRODUCT PARAMETER

Nominal switching temperature (NST) in 5°C

80 °C - 170 °C

Tolerance (standard)

±5K

Trip time (current at different trip times)

4-10 s

Thickness

3.7mm

Width

9.3mm

Length

23mm

Resistance to impregnation

suitable

Suitable for installation in protection class

PTI175

Rated current 250V AC cos ϕ = 1.0 / cycles

27.5A/ 500

Rated current 250V AC cos ϕ = 0.6 / cycles

18A/ 1000

Rated current 120V AC cos ϕ = 0.6 / cycles

18A/ 15000

Rated current 15V DC / cycles

30A/ 30000

Rated current 30V DC / cycles

15A/ 30000

Insulation voltage

1.5 KV

Contact resistance

≤ 50 mΩ

Vibration resistance at 10 ... 60 Hz

100 m/s²