ST11 Thermal protector

Power class: 1,6 A to 7,5 A

Type series: ST11 thermal protector

normally closed

resets automatically

with connector cables

Mylar-Nomex insulation

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ST11 Thermal protector

Main parts

1) Iron cover plate 2) stationary silver contact 3) spring disc

4) movable contact 5) housing 6) bimetal disc 7) Insulating paper

Construction

Stationary silver contact are riveted with iron cover plate.; The bimetal disc and spring disc are combined by steps on the movable contact. The current passes through the stationary silver contact to the movable contact, and then connects the housing through the spring disc to form a loop.

Function

When the circuit is normal, the movable contact is in close contact with the stationary silver contact under the pre-pressure of the spring disc. When the rated operating temperature is reached, the bimetal disc is deformed by heat, snaps into its inverted position and pushes the spring disc downwards. The contact is abruptly opened and the temperature rise of the device to be protected is disrupted.

After the circuit is disconnected, the ambient temperature begins to fall. When it reaches the defined reset temperature, the bimetal disc and the spring disc snaps back into its start position, the contacts will close again, and the circuit returns to the conduction state.

PRODUCT PARAMETER

Nominal switching temperature (NST) in 5°C

60 °C - 250 °C

Tolerance (standard)

(60-200) °C ±5K
(205-250) °C ±10K

Reverse switch temperature (RST) tolerance

≥ 35 °C (≤ 80°C NST)
-30K±15K (≥ 85°C ≤ 180° C NST)
-60K±15K (≥ 185° C ≤ 200° C NST)
120℃±15K (＞200°C NST)

Thickness

>4.3mm

Diameter

9.5mm

Length of the insulation cap

15mm

Resistance to impregnation

suitable

Suitable for installation in protection class

I+ll

Pressure resistance to the switch housing

500N

Standard connection

0.33 mm² / AWG22

Insulation voltage

2.0 kV

Available approvals

UL/VDE/CQC/CB

Operating voltage range AC/DC

up until 500 V AC / 14 V DC

(60-200)°C Operating temperature products

Rated voltage AC

250 V(VDE)
277 V(UL)

Rated current AC cos ϕ = 1.0 /cycles

2.5A / 10,000

Max. switching current AC cos ϕ = 1.0 /cycles

6.3 A / 3,000
7.5 A / 300

Rated current AC cos ϕ = 0.6 /cycles

1.6 A / 10,000

Rated voltage DC

12.0 V

Max. switching current DC /cycles

40.0 A / 5,000

(205-250)°C Operating temperature products

Rated current AC cos ϕ = 1.0 /cycles

2.5A / 1,000

Rated current AC cos ϕ = 0.6 /cycles

1.6 A / 1,000

Total bounce time

< 1 ms

Contact resistance

≤ 50 mΩ

Vibration resistance at 10 ... 60 Hz

100 m/s²

PRODUCT PARAMETER