A thermostat is device for maintaining a system (apparatus, machine, engine, etc.) at a relatively stable temperature. The first device was developed by Albert Butz in 1886 that gave birth to Honeywell. It allowed to order an air inlet door on a coal boiler to "regulate" its temperature. In 1906, Honeywell developed an already associated with a clock device, hence the birth of clock device (zone control thermostat).
Device has long been comprised of a bimetallic system which opens a circuit when the heat reached a certain stage and closed the circuit as soon as we descended below this temperature. In practice, it was as if there had been in fact two temperature setpoints neighboring thermal system with itself a certain inertia (similar to hysteresis in field of magnetism).
The effect of heater is switched on the room temperature in recent days is stored in a memory effect. When the indoor environmental conditions (eg open doors that are normally closed) or outdoors (by weather changes) change drastically, it will take some days before device optimally anticipates the need for heat.
Obviously these cranes work well only when hot water is pumped into system. When device in main room the boiler does not catch on, device has no effect. In systems with a modulating burner, circulates longer-lasting than in systems with an on-off control, so that hot water device valves with the use of a modulating burner, are more effective.
A desired temperature for a room can be a room device (often called room device) set. Device acts on the (central) heating system. The choice of type device is partly determines the energy consumption and the associated heating costs. Devices can be of different types: Conventional / or non-electronic device - By means of a mercury switch or electronic module is corrected by ambient temperature to be measured and comparing it with the set value.
The line of central temperature is the set point temperature and the differential d is the difference between the temperature which determines the state of off, and the one which determines the state of on. The time in on-off switching must be compatible with the equipment or fluid controlled: response times are too short can damage electrical equipment controlled (and generate noise on the power grid that does not comply with CE regulations on flicker) and are not therefore feasible with this type of adjustment. Device is therefore suitable to adjust the temperature of environments in which this varies slowly over time (civil environments, refrigerators ...).
In mechanical devices the sensitive element is a foil or a fluid in which the variation involves a thermal deformation and therefore is the same sensitive element which determines the state of switch. The sensor element can also be a bimetallic strip, which is constituted by two sheets of different materials joined together. Since the two materials have different expansion coefficients, a temperature change results in a curvature of foil which can then act directly as a switch.
In engines device opens the flow of cooling water with increasing temperature of cylinder head. In this case, the sensitive element is a wax and the opening temperature is between 70 and 90 degrees C. In these types device the sensitive element is typically a resistor whose resistance value is variable with temperature (for example an NTC thermistor), or a semiconductor device, (for example the IC LM31), which, inserted in an electronic circuit, controls the on-off state of a relay or other solid state device.
Device has long been comprised of a bimetallic system which opens a circuit when the heat reached a certain stage and closed the circuit as soon as we descended below this temperature. In practice, it was as if there had been in fact two temperature setpoints neighboring thermal system with itself a certain inertia (similar to hysteresis in field of magnetism).
The effect of heater is switched on the room temperature in recent days is stored in a memory effect. When the indoor environmental conditions (eg open doors that are normally closed) or outdoors (by weather changes) change drastically, it will take some days before device optimally anticipates the need for heat.
Obviously these cranes work well only when hot water is pumped into system. When device in main room the boiler does not catch on, device has no effect. In systems with a modulating burner, circulates longer-lasting than in systems with an on-off control, so that hot water device valves with the use of a modulating burner, are more effective.
A desired temperature for a room can be a room device (often called room device) set. Device acts on the (central) heating system. The choice of type device is partly determines the energy consumption and the associated heating costs. Devices can be of different types: Conventional / or non-electronic device - By means of a mercury switch or electronic module is corrected by ambient temperature to be measured and comparing it with the set value.
The line of central temperature is the set point temperature and the differential d is the difference between the temperature which determines the state of off, and the one which determines the state of on. The time in on-off switching must be compatible with the equipment or fluid controlled: response times are too short can damage electrical equipment controlled (and generate noise on the power grid that does not comply with CE regulations on flicker) and are not therefore feasible with this type of adjustment. Device is therefore suitable to adjust the temperature of environments in which this varies slowly over time (civil environments, refrigerators ...).
In mechanical devices the sensitive element is a foil or a fluid in which the variation involves a thermal deformation and therefore is the same sensitive element which determines the state of switch. The sensor element can also be a bimetallic strip, which is constituted by two sheets of different materials joined together. Since the two materials have different expansion coefficients, a temperature change results in a curvature of foil which can then act directly as a switch.
In engines device opens the flow of cooling water with increasing temperature of cylinder head. In this case, the sensitive element is a wax and the opening temperature is between 70 and 90 degrees C. In these types device the sensitive element is typically a resistor whose resistance value is variable with temperature (for example an NTC thermistor), or a semiconductor device, (for example the IC LM31), which, inserted in an electronic circuit, controls the on-off state of a relay or other solid state device.
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