How does a bimetallic thermal switch work?

How does a bimetallic thermal switch work?

The bimetallic strip consists of two thin strips of different metals, each having different coefficients of thermal expansion. Thermal expansion is the property of a metal to change its shape or volume with a change in temperature. The metal strips are connected along their length by fusing them together or riveting.

What is a BI metallic switch?

A bimetallic switch is a control engineering component which causes a certain action once a defined temperature is reached, e.g. switching off a process in order to avoid overheating.

What is bimetal in refrigerator?

Tip. Defrost bimetal thermostats prevent the harmful buildup of frost on refrigerator and freezer evaporators. These devices trigger a defrost heater that stops frost from forming on refrigeration evaporator coils, which helps keep the refrigerator and freezer running efficiently.

What happens when a bimetal device is heated?

each of these metals has a different rate of expansion and contraction when heated or cooled. the brass expands faster than the steel which causes the device to warp. the motion of the bimetal strip is then used to perform some useful task.

What is a thermal switch?

A thermal switch is an electromechanical device which opens and closes contacts to control the flow of electrical current in response to temperature change. The term “Thermal Cutoff Switch” generally refers to how the switch is used, ie.

What are some applications of the bimetal strip?

Usually steel and copper, or in some cases steel and brass is used in bimetallic strip. Two applications are: Used in fire alarms. Used in mechanical clocks to remove the error caused by temperature change.

Why is a bimetallic strip used in a thermostat?

Bimetallic strips are used in thermostats for measuring and controlling temperature. The strip is connected to a switch and as the temperature changes the strip flexes and opens or closes a contact. They are also used in ovens for measuring temperature.

What is the function of bimetal?

Bimetal strips are used in miniature circuit breakers to protect circuits from excess current. A coil of wire is used to heat a bimetal strip, which bends and operates a linkage that unlatches a spring-operated contact. This interrupts the circuit and can be reset when the bimetal strip has cooled down.

How do you adjust a bimetal thermostat?

Pull off thermostat cover and set thermostat a few degrees above room temperature. Slip the wrench onto the nut behind the coiled bimetallic element, hold the dial firmly, and turn until the mercury breaks contact. (The direction you’ll need to turn the nut varies between models.)

How does a thermostatic switch work?

Thermostatic switches, in essence, are controls that operate solely on the information given to them by measuring the temperature emitted from the device they control. When a setting for the switch is created, the switch either engages the device or disengages the device when the set temperature is reached.

What is ST-12 bimetal thermal switch?

ST-12 by SEKI Controls is thermal switches bimetal that has snap action, superior heat response, automatic reset, and non-phenolic insulation features. SEKI Controls – Manufacturing and offering Non-Phenolic Insulation St-12 Bimetal Thermal Switch it has Superior Heat Response, Automatic Reset Bimetal and Snap Action.

What are the characteristics of bi-metal immersion temperature switch?

Bi-metal immersion temperature switch. Probe Length: 1″. Circuit Form: SPST-NO. Electrical Connection: 6″ Wire Leads. Set Temperature: 190 °F. Set Temperature Tolerance: +/- 5 °F. Max… [See More] Key benefits: Good sealed. Small in size, normally closed thermal switch ST06 can be embedded inside the coil.

What are the specifications of the st09 bi-metal immersion temperature switch?

Bi-metal immersion temperature switch. Probe Length: 1″. Circuit Form: SPST-NO. Electrical Connection: 6″ Wire Leads. Set Temperature: 170 °F. Set Temperature Tolerance: +/- 5 °F. Max… [See More] Key benefits: The ST09 thermostat is a self-recovery temperature controller with a bimetallic temperature-sensing jump single-pole single-throw type.

What is a snap action bimetal thermostat?

Snap action bimetal thermostats open or close a circuit at a factory pre-set temperature. Typical Applications Include: Power supplies, amplifiers, engines, appliances, fans, freezers and vending machines. All have solder terminals except for QC, which are 0.250 quick connect. 125 VAC, 15 amps… [See More]