FI123679B - underfloor - Google Patents

Description

LATTIALÄM MITSTERMOST AATTI

FIELD OF THE INVENTION

Embodiments of the present invention are directed to an integrated floor heating-5 thermostat and an earth leakage protection structure.

BACKGROUND OF THE INVENTION

One way to arrange the heating of a house or room in a house is by using underfloor heating systems using electricity. Electrical underfloor heating systems are typically installed in kitchens, bathrooms or rooms that require additional heat (such as a cold basement, an accessory or children's playroom). The underfloor heating system can be implemented by installing heating elements under the floor surface. The electric heating elements are supplied in many different forms. They may be in the form of a single continuous-length cable, whereby the installer must spread the cable back and forth on the floor at predetermined intervals and make a return loop to close the circuit, or they may be arranged in a matt shape with the heating element preformed on the floor. Some high voltage cables have a built-in return, meaning that the person installing the cable has one end to connect. Some techniques consist of a loop with a beginning and an end.

In addition to the heating elements, the system may consist of a heating thermostat unit, a sensor or a sensor cable and wires connecting the heating element to the thermostat unit and the sensor or sensor cable to the thermostat unit.

δ ™ The sensor is often installed on the floor for temperature measurement purposes. The sensor can be 9, for example, a NTC (Negative Temperature Coefficient) resistor whose resistance δ 25 decreases as the temperature increases. The sensor is wired to the thermostat electrode and ankle in the thermostat unit. The thermostat unit typically switches the heating elements on / off using relays, depending on the floor temperature and the thermostat setting. Further or alternatively, the thermostat may comprise a sensor for measuring room temperature from room air, o

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30 In many countries, electrical regulations and standards require all electrical underfloor heating systems to be protected by a residual current device (RCD) typically rated at less than 30 mA.

2 An RCD is an electrical switching device that disconnects a circuit whenever it detects that the electrical current is not balanced between the conductor connected to the voltage source and the return neutral conductor.

The RCD may be mounted on the underfloor heating system as a separate unit or it may be mounted on a thermostat. One underfloor heating thermostat with a fault current protection is disclosed in EP 1953459A2. According to the patent application, the thermostat and the RCD are independent elements which are integrated together. However, due to this partially overlapping structure, the thermostat shown is relatively high in size, with a total depth of 10 about 46 millimeters, which is large to fit a standard wall mounting box having a depth of about 45 millimeters. In addition, the wiring for electricity and the sensor require additional space in the wall mounting box, resulting in a structure where the top level of the thermostat from the wall surface can be greater than 15-25 millimeters. In addition, installing the thermostat is cumbersome because the cable from the temperature sensor must be passed through an earth leakage circuit breaker so that the cable can be connected to the thermostat.

SUMMARY OF THE INVENTION

In accordance with aspects of the present invention, a structure is provided for reducing the size of an ice-current protected thermostat.

In at least some embodiments of the invention, a circuit layout is provided for mounting electrical components on the control unit.

This is achieved by a combination of the features mentioned in the independent claim. Similarly, the dependent claims describe other detailed embodiments of the present invention.

The features and advantages of the invention will become apparent from the following exemplary description of preferred embodiments of the invention only, with reference to the accompanying drawings.

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30 BRIEF DESCRIPTION OF THE DRAWINGS

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Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 is a schematic view showing the thermostat assembly, the cover and the wall on which the thermostat assembly can be mounted.

Figure 2 is a schematic view showing a wall mounted thermostat assembly.

Figure 3 is a schematic circuit diagram showing the first printed circuit board and some components on one side of the board.

Figure 4 is a schematic circuit diagram showing another printed circuit board and 10 of some components on one side of the board.

Fig. 5 shows a schematic view of the thermostat unit from the front to the other and from the side.

Figure 6 shows a photograph of a thermostat unit according to one embodiment and a ruler to indicate the size of the unit.

Figure 7 shows a photograph of another printed circuit board according to an exemplary embodiment.

Figure 8 shows a photograph of a first printed circuit board according to an exemplary embodiment.

Fig. 9 is a side view of a thermostat unit according to an exemplary embodiment 20.

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δ Figure 10 shows a photograph of an exemplary embodiment of the embodiment.

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Fig. 11 shows a schematic diagram of a thermostat, δ x Fig. 12 shows a schematic exploded view of a possible floor heating thermostat.

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“Structure including mechanics.

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DETAILED DESCRIPTION OF THE INVENTION

Referring first to Figure 1, an embodiment of the invention would be suitable as a wall mounted thermostat unit 1 as shown in Figure 1. The thermostat unit 1 according to embodiments of the invention comprises two printed circuit boards (PCBs) 30 and 20. In exemplary embodiments, PCBs 30 and 20 are dual-layer PCBs having components on both sides of the circuit boards, but it is also possible to: that in some embodiments, the second PCB is one-sided. For purposes of explanation, PCB 20 is referred to as the first PCB and PCB 30 as the second PCB in exemplary embodiments. In addition, orientation concepts such as "top" and "bottom" refer to the orientation of the device as seen in the drawings and do not limit its orientation in use.

The thermostat unit 1 is preferably dimensioned to fit into a standard wall socket 10 having a free internal diameter of 50-55 mm and an external diameter of 70-75 mm, depending on country-specific standards. The box 10 can be mounted on the wall 12 by making a hole in the outer surface 12 of the wall and inserting the box into the opening. Alternatively, the box 10 may be mounted on the wall structure before the outer surface 15 is mounted. The box 10 may be connected to some structural elements of the wall (not shown) by means of screws 14. The cabinet 10 may have metal or plastic parts 102 which allow the thermostat unit 1 to be securely mounted in the box. In addition, or alternatively, the thermostat unit could have holes to allow, for example, the use of screws to secure the unit to the box 10. Such holes 20 are typically located on the bottom of the thermostat. In one embodiment, there is a lid 3 which can be placed on one of the thermostat units to cover the box 10, and which can also be provided with means for adjusting the temperature and, for example, pressing the fault current button.

Fig. 2 shows an installed thermostat unit 1 in a mounting box 10. Fig. 2 25 shows that at least some embodiments of the invention allow fault current,

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g, i.e., constructing a residual current protected floor heating thermostat so that the thermostat protrudes 10-20 mm less than in the present solutions, when compared with the prior art, by clearly observing the surface of the wall 12. One of the terminals 20 of the first PCB of the thermostat unit 1 is connected 30, as shown schematically in FIG. Embodiments of the invention are not limited to a wall mounting box, but the proposed structure of the thermostat unit 1 also allows the construction of a relatively thin model to be equally well surface mounted thermostat.

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An exemplary structure of the thermostat and a circuit diagram of the components of the first PCB 20 and the second PCB 30 are shown with reference to Figure 3 and Figure 4.

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For example, connector 202 on first PCB 20 may have a 7-pin connector such as MVE25 from Euroclamp ™. The outgoing / inlet wires 40 of thermostat 1 may be connected to terminal 202. According to at least some embodiments, the main power to a heating system consisting of thermostat unit 1 and heating elements 5 and a floor sensor is fed to pin X7 (step (L)) and X6 (zero). (N)). Typically, the rated voltage in Europe is about 230VAC at 50Hz. In some areas, such as North America, the rated voltage is approximately 110VAC at 60Hz.

Connector 202 also supplies electricity to the heating element via, for example, pins X5 10 and X4 if control relay 206 is turned on. The control relay 206 can be, for example, a relay RT334024 from Tyco Electronics ™ which is capable of switching on and off currents / voltages of 16A / 250VAC. Preferably, the relay 206 is mounted on the circuit board in such a direction that the switch portion, i.e. the high voltage portion, is closer to the terminal 202. The control signal then passes in the lower part of the PCB from the direction of aspect 15 of FIG. This enables the electrical design of the first PCB 30 in such a way that the high voltage electronics is located substantially in the second left corner of the PCB from the direction of Figure 3. In one embodiment, the relay is controlled by a microcontroller IC (integrated circuit) 302 based on measurements from the sensor. Microcontroller IC 302 may be, for example, an NXP ™ microcontroller, such as the LPC1100, which is based on an ARM ™ Cortex-MO processor and has a plurality of analog-to-digital (AD) converters, among other features. Said AD converters are used to determine the temperature level by measuring the power supply through the sensor NTC relative to the reference temperature level which can be set by adjusting resistor 304 on PCB 30. A control signal from IC 302 to relay can be supplied to the first PCB 20 via connector 216. The signal to the sensor can be supplied via terminal 216. In one embodiment of the invention, the floor sensor is preferably coupled to pins X1 and X2 of connector 202 o for placement at a maximum distance from the main current ob (coupled to pins X7 and X6). A further advantage of enabling connection of the temperature sensor to terminal 202 is that the thermostat is easy to install compared to prior art solutions where the cable from the temperature sensor must be

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σ> g Additional components on the first PCB 20 may have a capacitor 208 which? generates voltage to the thermostat portion of the product, and miscellaneous components 210 such as capacitors, resistors, transistors, diodes, and other active and passive components. Although the figure shows components only on one side, PCB 20 and PCB 30 may also have components on one side.

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A central component from a fault current protection point of view is a solenoid switch component 204 mounted on a first PCB 20. The solenoid component 204 may be, for example, a WA M2ML solenoid from Western Automation Research and Development Ltd. According to at least some embodiments, the solenoid switch component is coupled such that the main current from pins X7 and X6 is first supplied through a measuring coil measuring residual current, and then through component 204. In the Vi current situation, the control signal from the electronics connected to the residual current device (RCD) cuts off the main power. In one embodiment, the RCD electronics is contained in another PCB 30. One way to obtain a signal from the RCD is through the connector 21610.

The residual current device related electronics consists of an integrated circuit 306 for fault current detection, a test / measurement winding 308, and miscellaneous passive and active components 310. The circuit 306 may be, for example, WA05GC from Western Automation Research and Development Ltd. Test / Measurement Coil 308 may be, for example, a component from Western Automation Research and Development Ltd. The main current from the pins X6 and X7 of the connector 202 of the first PCB 20 is fed through the pins 324 and 322 to the second PCB 30. The pins 324 and 322 pass through a measuring coil 308 as shown in Figure 4. The pins 324 and 322 are electrically coupled to the conductor lines 315 and 314 to the pins 214 and 212, respectively. The electricity 20 is fed back to the first PCB 20 via pins 214 and 212 and then coupled to the switch component 204 as previously described. In the case of a fault current, the circuit 306 pinches the component 204 to turn off the power. According to embodiments, there is a space 312 between the conductive conductor lines 314 and 315, preferably a space of at least 4 millimeters to comply with certain security standards. The second PCB preferably has a hole 316 (Fig. 4) to enable the use of a reset current 213 (see Fig. 5) of the switch 204, δ ^ According to at least some embodiments of the invention, the PCB 20 and PCB 30 are approximately equal in size. At least in some embodiments, the PCBs can be attached to one another in a '' piggy bag '' style. 30 using pins 214, 212, 226, 227 and connector 216. Said pins may be soldered, initially prior to connecting the second and the first to either the second and / or the first PCB. After the second and first final assembly, the other end of the pin can also be soldered, which ensures better conductivity. The counterpart of connector 216 (also designated 216) may be on either the second or the first PCB. For example, connector 216 may have 8 pins to allow communication between the second 30 and the first 20 PCBs 7. The combination of the second PCB 30 and the first PCB 20 is referred to as a thermostat unit 1 in one embodiment.

Figure 5 further shows the thermostat unit 1 facing the first PCB 30 and from the left (view A) and the second (view B). As can be seen, the second PCB 20 and the first PCB 30 are connected in a stack. In addition to the components previously disclosed, there may be, for example, a switch 326 soldered to the other side of the second PCB 30 to test, for example, fault current functionality. As can be seen, a solenoid switch component 204 may be coupled to a mechanical switch 213 to reset the RCD.

Further explanations of the embodiments are shown in Figures 6, 7, 8 and 9, which show photographs of one embodiment of the invention. As can be seen in Figures 9 and 6, the size of the thermostat unit with integrated fault current detector is significantly smaller than in prior art arrangements.

Figure 10 shows a photograph of an exemplary thermostat, viewed mainly from the direction of the surface layer 30 of the second PCB 15 for purposes of clarification. Manual reset pin 213 is accessed through aperture 316 in second PCB 30. Figure 11 shows a schematic circuit diagram of a thermostat. The components in the second PCB are drawn inside the dotted line. Other components are mounted on the first PCB 20. The main current (L and N) is supplied through terminals X7 and X6 of terminal 202 20. Electricity is supplied from terminal 202 to the second PCB 30 and back to the first PCB 20 via coil 308. Coil 308 is coupled to circuit 306 for detecting residual current leakage in the system. As shown in Fig. 11, circuit 306 provides a control signal to the circuit breaker component 204. In normal operation, power is applied to relay 206. Relay 206 is controlled by ≤250 microcontroller 302. Microcontroller 302 is connected through pins X1 and X2 to a sensor that measures floor temperature. Pins X4 and X5 are used to supply electricity to the heating element.

Fig. 12 is a schematic exploded view of a possible construction of a floor heating thermostat including mechanics. The bottom cover 510 is typically mounted σ> 30 on the electrical box 10. The middle cover 508 can be used to increase the surface area o and the air gap for the electrical components of the PCBs 20 and 30. Knob 506 can be used to turn adjusting resistor 304 to set the desired temperature. 500, 502 c and 504 are decorative covers for the thermostat. Parts 500, 502, 504, 506 and 508 may together form the lid 3 of Figure 3.

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As stated above, according to the invention, a thermostat with a residual current device comprises at least two printed circuit boards (PCBs), a first PCB 20 and a second PCB 30, and that relay 206, connector 202 and circuit breaker 204 are connected to first PCB 20 and the measuring coil 308 is coupled to the second PCB 5 30. In at least some embodiments of the invention, the residual current detection logic components are attached to the second PCB. The residual current detection logic components comprise at least a circuit 306, such as the WA05GC from Ward Industries ™ or the like, which is connected to the measuring coil 308. This component circuit pattern provides a very compact thermostat structure.

In at least some embodiments of the invention, the temperature control logic is coupled to the second PCB 30. Also, a capacitor configured to supply voltage to the thermostat circuit is disposed on the first PCB 20.

In at least some embodiments of the invention, connector 202 comprises a plurality of terminals for connecting a terminal cable and at least a load cable, a floor temperature sensor cable, a temperature reduction signal, and a thermostat heating cable connector. Because all external cable connections are in one easy-to-access part of the thermostat, installation of the thermostat for use has been made easy and quick.

As mentioned above, the PCBs used may have components on one or both sides of the board. According to at least some embodiments of the invention, the first PCB 20 comprises a base layer 230 and a surface layer 232, and that the second PCB 30 comprises a base layer 330. In this connection, the terms base layer and top layer indicate that the base layer is on one side and The base layer 330 of the PCB 30 is toward the top layer 232 of the first PCB 20 and the top layer 332 of the PCB 30 is away from the first £ 25 of the PCB 20. The relay 206, the connector 202 and the circuit breaker 204 are connected to the bottom layer 230 of the first PCB 20 and that the measuring coil 308 is connected or located between the bottom layer 330 of the second PCB 30 and the top layer of the first PCB 20.

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In at least some embodiments, the resistor 304 for setting the temperature level σ> 30 is coupled to the second PCB 30. The resistor 304 is connected, at least in some embodiments, to the bottom layer 330 of the second PCB 30, i.e. the first 5 PCBs 20 and Between the PCB 30 so that the resistor does not increase

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total height. To enable the resistor to be adjusted, the second PCB 30 comprises an opening for the lever extending through the cover 3 to engage the resistor 304 35 through the second PCB 30 and the cover 3.

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According to at least some embodiments of the invention, the first PCB 20 and the second PCB 30 are electrically connected by two pairs of connector wires to conduct high voltage between the first PCB 20 and the second PCB 30 to provide a high voltage loop from the first PCB 20 to the second PCB 30. . In some embodiments of the Kek-5 invention, said loop has no purpose other than to pass through the measuring coil so that residual current, i.e. a malfunction of the heating system, can be detected. The thermostat further comprises a pair of connector lines 226 and 227 for supplying operating voltage for the RCD from the first PCB 20 to the second PCB 30. Additionally, a plurality of auxiliary connector lines 216 conduct low voltage and 10 control data between the first PCB (20) and the second PCB (30). .

According to the invention, the circuit breaker 204 comprises a movable body member 234. The movable body member comprises metal connectors arranged to move back and forth against the fixed contacts, which contacts are connected to the bottom layer 230 of the first PCB 20 controlled by a solenoid 15 236 attached to the first PCB 20. As mentioned above, one suitable circuit breaker, or solenoid switch component, for use in embodiments of the invention is a WA M2ML solenoid from Western Automation Research and Development Ltd. In addition, the circuit breaker 204 comprises a circuit breaker manual reset pin 213. The manual reset pin 213 is arranged to extend through the opening 316 in the second PCB and through the lid 3 so that it can be operated e.g. by pressing from the outside of the thermostat.

According to some embodiments of the invention, the surface layer 332 of the second PCB 30 comprises a test weight button 326 for testing the residual current detection functionality. This allows the residual current detector and circuit breaker 204 to be tested as they should.

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The thermostat according to at least some embodiments of the invention comprises a green LED and a red LED to indicate the operating status of the control relay (206). The green LED and red LED are preferably coupled to the surface layer x (332) of the second PCB (30).

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g> 30 In some embodiments of the invention, the main current from pins X6 and X7 o of connector 202 is fed through first connector lines 324, 322 to a second PCB 30, en-

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5, 324 and 322 being arranged to pass the measuring coil

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308 and electrically coupled via the connector wires 314 and 315 of the second PCB 30 to the second connector wires 214, 212 and back to the first PCB 20 via the second connector 35 wires 214, 212, and then fed to a circuit breaker 204 connected to the first To PCB 20. This new design and circuit design allows for efficient and reliable detection of residual current and circuit breakage in a very small space and in compliance with safety regulations.

In at least some embodiments of the invention, the first connector wires 322 and 324 5 are effectively long pins from the connector 202 and the second connector wires 212 are 214 are rigid metal pins. The connection cables may be made of steel, copper or any other suitable metal with high conductivity. It should also be noted that the first and second connector pins may be made of a different material. The length of the first connector lines 322 and 324 and the second connector lines 212, 214 is always 10 to 12 mm in some embodiments of the invention. In at least some embodiments, the first connector lines 322 and 324 and the second connector lines 212 and 214 are arranged parallel to each other.

According to at least some embodiments of the invention, the first connector lines 322 and 324 are arranged such that the distance between the connector lines is greater than or equal to 4 mm. Similarly, the second connector lines 212 and 214 are arranged such that the distance between the connector lines is greater than or equal to 4 mm. By having said distance greater than or at least equal to 4 mm, it is possible to reduce the risk of electrical breakdown between the connector wires.

In at least some embodiments of the invention, the first connector wires 322 and 324 20 are part of the connector 202 and are arranged to extend through the first PCB 20. This reduces the amount of solder joints needed and thus less heat is generated and voltage drops are reduced.

According to at least some embodiments of the invention, the first connector wires 322 and 324 and the second connector lines 212 and 214 are attached to the first PCB 20.

The first connector leads 322 and 324 and the second connector leads 212 and 214 are further arranged to be electrically connected to the second PCB 30 by extending through the openings in the second PCB 30 so that the edges of the openings and the connector leads 322, 324 212 and 214 electrical connections are formed.

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The distance between the top layer 232 of the first PCB 20 and the bottom layer g 30 330 of the second PCB 30 is 7 to 11 mm, at least in some embodiments of the invention.

This distance allows the components to fit into the space between the first PCB 20 ° and the second PCB 30 while still allowing for a compact overall height of the thermostat.

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As mentioned above, according to the invention, the thermostat comprises a first printed circuit board (PCB) 20 on which the relay 206, a connector 202 and a circuit breaker 204 are located, and a second PCB 30 on which the measuring coil 308 is located and the circuit breaker 204 is connected to the first PCB 20. The relay 206 5 is connected adjacent to the connector 202 so that the contacts of the relay are facing the connector. This circuit pattern structure reduces the length of the high voltage connections on the first PCB and thus reduces heat generation in the thermostat.

According to at least some embodiments of the invention, the relay 206 is located on the first PCB 20 between the capacitor 208 and the circuit breaker 204. The advantage of this 10 circuit pattern is that the relay 206 and the circuit breaker 204 are adjacent to each other so that the high voltage components are close to each other, thereby reducing the length of the high voltage connections on the first PCB.

In at least some embodiments of the invention, the spacing between the relay 206 and the pins of the connector 202 to which the relay 206 is connected is less than 8 mm.

As mentioned above, the thermostat according to embodiments of the invention is a floor heating thermostat with residual current detection functionality and a circuit breaker in the thermostat.

Other embodiments of the invention include the addition of a room temperature sensor preferably to the second PCB 30. Embodiments of the structure allow accurate operation of said sensor 20 as it is located as far as possible from the heat generated by the first PCB 20. In addition, power components such as relay 206, are far from the built-in temperature sensor for more accurate operation.

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In addition, the second PCB 30 may include light emitting diodes (LEDs) for displaying to the users of the thermostat unit, e.g., through the aperture of the lid 3 or through the transparent portion of the lid 39, for example. The microcontroller IC 302 may include or control a wireless or wired communication unit. Said unit can be used for remote monitoring and control of the thermo-static unit. An example of a wireless communication unit is a Bluetooth or wireless local area network. An example of a wired communication protocol to use is a local area network over power lines or a separate communication network such as Ethernet.

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It should be understood that a similar design can be used for other thermostats that require an earth leakage protector than a floor thermostat. As an example, a similar structure could be used for a thermostat that controls the heaters in the house.

It should be understood that any feature disclosed for any one embodiment may be used alone or in combination with other features disclosed, and may also be used in combination with one or more features of any other embodiment, or any combination of any of the features with another embodiment. In addition, similar devices and modifications not shown above may also be used without departing from the scope of the invention as defined in the appended claims.

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Claims (6)

An underfloor heating thermostat provided with a residual current device comprising a thermostat relay (206), a connector (202), a capacitor (208), a circuit breaker (204) and a measuring coil (308), characterized in that the thermostat comprises a first printed circuit board (PCB). ) (20) to which the relay (206), the connector (202) and the circuit breaker (204) are connected, and the second PCB (30) to which the measuring coil (308) is connected, and that the relay (206) is connected to 202) adjacent such that the relay contacts face the connector, and that the circuit breaker (204) comprises a movable body member (234), a movable body member comprising metal connectors and being reciprocally reciprocally connected to the bottom layer (230) of the first PCB (20). against fixed contacts. A thermostat according to claim 1, characterized in that the first PCB (20) comprises a base layer (230) and a surface layer (232) and that the second PCB (30) comprises a base layer (330) which is a surface layer of the first PCB (20). 152, and away from the first PCB (20), and that the relay (206), the connector (202) and the circuit breaker (204) are located on the bottom layer of the first PCB (20). (230), and that the measuring coil (308) is disposed on the bottom layer (330) of the second PCB (30). The thermostat according to claim 1 or 2, characterized in that the relay 20 (206) is located on the first PCB (20) between the capacitor (208) and the currents between the splitter (204). Thermostat according to any one of the preceding claims, characterized in that the adjusting resistor (304) for setting the temperature level is connected to the second PCB (30). δ ^ 25 A thermostat according to claim 4, characterized in that the adjusting resistor CD 9 (304) is disposed on the bottom layer (330) of the second PCB (30) and that the second PCB (30) 'comprises an opening for the lever : | (30). c \ j Thermostat according to any one of the preceding claims, characterized in that the distance between the pins of the relay (206) and the connector (202) to which the relay (206) is connected is less than 8 mm.