1. KSD301 temperature protector’s Principle and structure
The main principle of KSD series thermostat is that one function of bimetal discs is snap action under the change of sensing temperature. The snap action of disc can push the action of the contacts through the inside structure, and then caused on of off the circuit finally. The main characteristic are the fixation of working temperature, the reliable snap action, less flashover longer working life and less radio interference.
2. KSD301 thermostat’s specification
2.1. Electrical Rating: AC 125V max 15A; AC250V 5A 10A 15A max 16A
2.2. Action Temperature: 0~300 degree
2.3. Recovery and action temperature difference: 10 to 25 degrees, or according to client's request.
2.4. Temperature deviation: 23 / 35 / 310 degree or according to client's request
2.5. Circuit resistance: ≤50mΩ (Initial value)
2.6. Insulation resistance: ≥100mΩ (DC500V Normal State)
2.7. Dielectric Strength: AC50Hz 1500V / min, no breakdown blinding (NormalState)
Life cycle: ≥100000
2.8. Normally closed or open
2.9. Two kinds of mounting bracket: movable or immovable
2.10. Terminal
a. Terminal type: 187series of 4.8*0.5mm and 4.8*0.8mm, 250 series of 6.3*0.8mm
b. Terminal Angle: bending angle: 0~903C optional
2.11. Two kinds of body: plastic or ceramic.
2.12. Two kinds of temperature sensor face: aluminium cap or copper head.
3. Difference of auto reset type and Manual reset type
3.1. Manual reset type: Temperature sensing components consist of bimetallic strip. When the temperature reached the action temperature range, it will jump quickly and the movable disc disconnects. When the temperature declines to a fixed temperature point, the contact point cannot reset until reconnecting the circuit by pushing the reset button. And then the contact points recover, reaching a purpose of connecting or disconnecting the circuit and restarting the circuit by manual reset. (Kindly reminder: 1.This type of manual reset thermostat can reset when the temperature declines 20 2C after snap action by pressing the reset button. And 4~6 N will be advisable; please don’t use too much strength. 2. To ensure the normal function, the distance between the reset button and the close cover should not be less than 20.4mm. )
3.2. Manual reset type: Temperature sensing components consist of bimetallic strip. When the temperature reached the action temperature range, it will jump quickly and the movable disc disconnects. When the temperature declines to a fixed temperature point, the contact point can auto reset and start working.

Temp	Action	reset	Temp	Action	Reset
30	30±3℃	≥15℃	125	125±3℃	110±5℃
35	35±3℃	20±5℃	130	130±3℃	115±5℃
40	40±3℃	25±5℃	135	135±3℃	120±5℃
45	45±3℃	30±5℃	140	140±4℃	120±5℃
50	50±3℃	35±5℃	145	145±4℃	125±5℃
55	55±3℃	40±5℃	150	150±5℃	130±5℃