KSD301 S.P.S.T thermostat working principle
Operation Principle
KSD301 snap action thermostat series is a small-size bimetal thermostat series with a metal cap, which belongs to thermal relays’family. The main principle is that one function of bimetal discs ls snap action under the change of sensing temperature. The snap action of disc can push the action of the contacts through the inside structure, then caused on or Off of the circit finally. The main characteristics are the fixation of working temperature, the reliable snap action, less flashover, longer working life and less radio interfernce
Cautions
1. The thermostat should work in environments with humidity not higher than90％. free of caustic. flammable gas and conducting dust.
2. When the thermostat is used to sense the temperature of solid items. its covel should be clung to the heating part of such items. Meanwhile. heat-comducting stilicon grease or other media of similar nature should be applied in to the cover surface.
3. The top of the covel must not be pressed to sink or be distored so as to avoid adveres effect on the thermostat’s temperature sensitivity or its other functions.
4. Liquids must be kept out of the Thermostat’s inner part, The base must avoid any foree that could lead to crack；it should be kept clear and away from the pollution of electric substance to prevent insulation weakening that leads to shortclrcuited damages.
Electric Ratings：AC250V 5A/AC120V 7A(Resistive load)
AC250V 10A(Resistive load)
AC250V 16A(Resistive load)
Electric Strength：No breakdown and flashover underAC 50Hz 2000V for one minute
Inslation Resistance：>1OOMQ(with a DC500V megger)
Contacts Form：S.P.S.T. Division to three types：
1. Closes in room temperature. Opens at temperature rise. colses at temperature decreasing.
2. Opens in room temperature. Closes at temperature rise. Opens at temperature decreasing.
3. Closes in room temperature. Opens when the temperature rise. closes at temperature decreasing.
The action of close will be fin ished through manual reset.
Earthing Methods：by the connection of the metal cap of thermostat and the earth-connect metal part of appliance.
Working Temperature Tolerance and Working Life
Min。 Temperature Differential
Note：1．The above temperature differential is the differential between open temperature value and closed temperature value．The max．temperature differential in our factory is 70℃~100℃。
2．In addition。we can manufacture thermostats up to the special requirement of characteristics and dimension from our clients．
Introduction：（KSD301, KSD9700 temperature control switch Temperature sensing Speed）
KSD301 snap action thermostat series is a small-size bimetal thermostat series with a metal cap, which belongs to thermal relays’family. The main principle is that one function of bimetal discs ls snap action under the change of sensing temperature. The snap action of disc can push the action of the contacts through the inside structure, then caused on or Off of the circit finally. The main characteristics are the fixation of working temperature, the reliable snap action, less flashover, longer working life and less radio interfernce
Cautions
1. The thermostat should work in environments with humidity not higher than90％. free of caustic. flammable gas and conducting dust.
2. When the thermostat is used to sense the temperature of solid items. its covel should be clung to the heating part of such items. Meanwhile. heat-comducting stilicon grease or other media of similar nature should be applied in to the cover surface.
3. The top of the covel must not be pressed to sink or be distored so as to avoid adveres effect on the thermostat’s temperature sensitivity or its other functions.
4. Liquids must be kept out of the Thermostat’s inner part, The base must avoid any foree that could lead to crack；it should be kept clear and away from the pollution of electric substance to prevent insulation weakening that leads to shortclrcuited damages.
Electric Ratings：AC250V 5A/AC120V 7A(Resistive load)
AC250V 10A(Resistive load)
AC250V 16A(Resistive load)
Electric Strength：No breakdown and flashover underAC 50Hz 2000V for one minute
Inslation Resistance：>1OOMQ(with a DC500V megger)
Contacts Form：S.P.S.T. Division to three types：
1. Closes in room temperature. Opens at temperature rise. colses at temperature decreasing.
2. Opens in room temperature. Closes at temperature rise. Opens at temperature decreasing.
3. Closes in room temperature. Opens when the temperature rise. closes at temperature decreasing.
The action of close will be fin ished through manual reset.
Earthing Methods：by the connection of the metal cap of thermostat and the earth-connect metal part of appliance.
Working Temperature Tolerance and Working Life
| T（WorkingTemp） | OPEN （Open Tolerance） | CLOSE （CloseTolerance） | （Max Working Temp） | （Working Life） |
| ≤150℃ | ±3℃ | ±6℃ | 190℃ | 100,000次（cycles） |
| 151℃-170℃ | ±4℃ | ±8℃ | 210℃ | 30,000次（cycles） |
| 171℃-210℃ | ±5℃ | ±10℃ | 250℃ | 16,000次（cycles） |
| （Manual reset type） | ±3℃ | （Manual reset type） | 190℃ |
| （WorkingTemp） | （Common Diff） | （Limit Min.Diff） |
| ≤100℃ | 17℃ | 8℃ |
| 101℃-130℃ | 17℃ | 8℃ |
| 130℃-155℃ | 17℃ | 8℃ |
| 156℃-175℃ | 25℃ | 8℃ |
| 176℃-190℃ | 30℃ | 8℃ |
| >190℃ | 35℃ | 8℃ |
2．In addition。we can manufacture thermostats up to the special requirement of characteristics and dimension from our clients．
Introduction：（KSD301, KSD9700 temperature control switch Temperature sensing Speed）
