GB2564512A

GB2564512A - Radio power switching

Info

Publication number: GB2564512A
Application number: GB1805217.5A
Authority: GB
Inventors: Fairall John
Original assignee: Rf Solutions Ltd
Current assignee: Rf Solutions Ltd
Priority date: 2018-03-29
Filing date: 2018-03-29
Publication date: 2019-01-16
Anticipated expiration: 2038-03-29
Also published as: GB2564512B; GB201805217D0

Abstract

A radio power switching system 4 comprising a controller 18, transmitter (figure 3) and receiver 4, where the transmitter and receiver 4 are coupled to a controller 18 and establish a radio frequency channel 21 to be controlled by the transmitter and receiver at either end of the channel in place of a switched live voltage; wherein the receiver is connected to a controller; wherein the controller is coupled to a switch 28 to turn on a mains supply voltage; where a radio signal is transmitted along the radio frequency channel, from the transmitter to the receiver; and wherein the received radio signals are fed into the controller, prompting it to activate the switch. The controller, transmitter, receiver and switch may be arranged to form part of an integral transceiver unit which is able to both transmit and receive radio signals.

Description

RADIO POWER SWITCHING

This invention relates to radio power switching.

Background of the Invention

During the installation of electrical apparatus, commercial or domestic, it can often be required to install an additional cable which carries a switchable ‘live’ signal from a control switch to the electrical appliance being installed. There remain many applications where this additional live switching cable is required. A typical example of such an application could be a water pump that requires switching on or off from some considerable distance away from its control switch. Another example may be the desire to switch a set of lights that are located in a separate building entirely.

For these types of electrical apparatus installations, where a switched live cable is required, the installation of the cable can often require a considerable amount of time, effort and expense in the form of extensive excavation to provide a pathway for the cable; digging a trench to bury the live switching cable may form one example of such excavation required.

In any case, the cost associated with the deployment of the switched live cable remains significant for electrical apparatus which is installed at a modest distance from the control switch.

The present invention aims to overcome or at least ameliorate one or more of the problems set out above.

Summary of the Invention

In particular, the present invention relates to a radio frequency (RF) power switching system, which allows the remote control of electrical apparatus by replacing a conventional ‘Live’ switching cable with an RF channel, with either end of the channel controlled by a transmitter and receiver; the present invention replicates and replaces the need for a live switching cable to supply the live switching signal to the desired electrical apparatus.

In a first aspect of the invention, there is provided apparatus for the remote control of electrical apparatus by way of a transceivable switching signal using an RF system where, the switching signal travels along an RF channel and where the apparatus comprises a transmitter unit and receiver unit which can be ‘paired’ together to allow uni-directional communication from the transmitter unit to the receiver unit.

The provided apparatus replaces a physical cable with a radio frequency channel, whereby the physical cable provided a channel for a live switching signal between the electrical apparatus and corresponding control apparatus.

In a second aspect of the invention, there is provided apparatus for the remote control of electrical apparatus by way of a transceivable switching signal using an RF system whereby, the apparatus comprises one or more transmitter units which are paired to a single receiver unit to allow uni-directional communication from the transmitter units to the single receiver unit.

In a third aspect of the invention, there is provided apparatus for the remote control of electrical apparatus by way of a transceivable switching signal using an RF system where, the apparatus comprises two identical transceiver units that can be ‘paired’ together to allow bidirectional communication between the pair of transceiver units.

Brief Description of the Drawings

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

Figure 1 is a front view of the radio power switching system;

Figure 2 is a front view of the hardware of the radio power switching system;

Figure 3 is a circuit block diagram of the transmitter unit;

Figure 4 is a circuit block diagram of the receiver unit;

Figure 5 is a cross sectional front view of the radio power switching systems connections;

Figure 6 is a front view of the receiver unit and a magnet;

Figure 7 is a front view the radio power switching system showing the state change of the switched signal;

Figure 8 is front view of the radio power switching system showing the state change of the switched signal for a many to one system;

Figure 9 is a front view of the hardware of the transceiver unit;

Figure 10 is a circuit block diagram of the transceiver unit;

Figure 11 is a cross sectional front view of the transceiver unit’s connections; and

Figure 12 is an overall system view of the radio power switching system implemented with a central heating system.

Detailed Description

With reference to Figure 1, apparatus for a radio power switching system comprises a transmitter unit 2 and a receiver unit 4 which are used to replace a conventional live switching cable which typically caries a live switching signal.

With reference to Figures 2 and 3, the transmitter unit 2 typically has power supply circuitry 16, a low voltage micro-controller control circuit 18, an RF transceiver 20 with an integral antenna 21, indicator LEDs 22 and unit screw terminals 24 for voltage input and output connections to the surrounding unit circuitry. The RF transceiver 20 is coupled to both the micro-controller control circuit 18 and integral antenna 21.

The power supply circuitry 16 operates from preferably a 110 - 230 V ac supply and generates a 3 V DC supply to the micro-controller control circuit 18 and RF transceiver 20. The microcontroller control circuit 18 performs logical functions, operations, diagnostics and control functions required for the rest of the unit to function as intended. The RF transceiver 20 operates preferably in the ISM Licence Exempt band of 868 or 915 MHz with the RF transceiver 20 antenna integrated internally such that the transmitter unit remains self-contained and has no protruding elements apart from the cable gland 7. The indicator LEDs 22 provide a visual indication of when a radio signal has been transmitted and illuminate when an RF signal is being transmitted.

With reference to Figures 2 and 4, the receiver unit 4 typically has power supply circuitry 16, a low voltage micro-controller control circuit 18, an RF transceiver 20 with an integral antenna 21, indicator LEDs 22, a reed switch 26, relay 28 changeover contacts and unit screw terminals 24 for voltage input and output connections to the surrounding unit circuitry, with this circuitry functioning in a similar fashion to that of the transmitter unit 2. Here, the LED’s 22 illuminate when a signal is being received from the transmitter unit 2. The reed switch 26 allows a user to induce changes in the receiver unit 4 without physically touching any of the unit’s 4 circuitry by way of a magnet 14. The relay 28 allows for the safe switching of the high voltage output of the receiver unit 4, allowing the rest of the unit’s circuitry to be isolated from the high voltage levels.

With reference to Figure 5, the transmitter unit 2 is able to receive the supply cable 6a, comprising of a switching live in 8 and neutral 10a connections, which can connect to the transmitter unit 2 through the cable gland 7a. The switching live in 8 and neutral 10a connections are connected to the corresponding unit screw terminal 24a inputs of the transmitter unit 2.

For the receiver unit 4, the supply cable 6b is connected in the same way as the transmitter unit 2, through the cable gland 7b, connecting the permanent live in 9 and neutral 10b connections to the unit screw terminals 24b. A second supply cable 6c is connected through a second cable gland 7c allowing the two output connections, neutral 10c and switching live out 12, to be connected to the unit screw terminals 24b, supplying a given load with these output connections whereby, the load is typically an electrical appliance and or apparatus.

Advantageously, the various input and output connections required for the operation of both the transmitter and receiver units have been simplified and connected to the screw terminals 24 allowing for quick and simple installation of the transmitter unit 2 and the receiver unit 4 to a desired electrical appliance. By simplifying the input/output connections of each unit to three cable glands 7 or ‘nodes’, one for the transmitter unit 2 and two for the receiver unit 4, the requirement for a qualified person to install these devices is not necessarily needed. No preemptive understanding is necessary for a user to install these devices; the simplified 3 node input/output design allows for a ‘plug in and play’ installation of the transmitter unit 2 and receiver unit 4 by following the instructions provided.

Further to the simplified ‘plug and play’ design described above, a transmitter unit 2 and a receiver unit 4 may be pre-paired together such that when the user receives the pair of units (2,4), it is not necessary for the user to pair the units (2,4) together. This pre-paring of transmitter and receiver units (2,4) further facilitates the simplicity of installing these devices with the user’s desired electrical apparatus.

With reference to Figure 6, for the RF channel to be established, the transmitter unit 2 must first be paired with the receiver unit 4. This is achieved using the reed switch 26 which allows a user to put the receiver unit 4 into differing modes of operation without physically touching any of the receiver unit 4 circuitry, by using a magnet 14. Here, the user can manually place a magnet 14, briefly, in close proximity to the receiver unit 4; with a voltage supply connected and a magnet briefly in close proximity, the receiver unit 4 is now put into a pairing state mode. Subsequent interaction of the magnet and receiver unit 4 may cause the unit 4 to cycle through the different modes which have been pre-programmed onto the unit’s storage memory. Such a mode may be that of a Self Test mode whereby, the unit operates all of its outputs to verify circuit function; a transmitted RF signal can be captured on a spectrum analyser to verify the RF signal is functioning as intended.

With the receiver unit 4 now in pairing mode, applying a mains supply voltage for a short period of time, around two seconds, to a transmitter unit 2 allows an RF channel to be established with the transmitter unit 2 whereby, both units can now be considered paired together. In this way, additional transmitter units, may be paired with the same receiver unit 4 allowing for a ‘many to one’ set up of transmitter units and receiver unit 4; the additional transmitter units can be added, sequentially, by using the same method as described above for each transmitter unit 2. The receiver can ‘learn about’ more than one transmitter unit. To erase a transmitter unit 2 from a paired receiver unit 4, the magnet 14 must be held in close proximity to the reed switch 26 of the receiver unit 4 for an extended period of time; preferably 10 seconds.

With reference to Figure 7, a paired transmitter unit 2 and receiver unit 4 can be seen in two different states; the switching live in 8 signal switched off and the same signal switched on; ‘switching’ the signal. With the switching live in 8 input signal switched off, the transmitter unit 2 transmits a radio signal 5 OFF’ command to the receiver unit 4 which causes the switching live out 12 output signal to remain or be turned off. When the switching live in 8’ input signal is switched on, the radio signal 5’ transmitted by the transmitter unit 2’ now instructs the receiver unit 4’ to switch on the switching live out 12’ output signal with an ON’ command; with the ON command received, a voltage is applied to the relay 28 which then ‘activates’ the output signal 12’ switching it on.

As the switching live in 8 input signal of the transmitter unit 2 is toggled, so too is the relay 28 and, therefore, the switching live out 12 output signal also. In this way, electrical appliances and or apparatus connected to the receiver unit 4, as a load, can be remotely controlled by the transmitter unit, thus replacing the need for a switching live cable. Additionally, with the switching live in 8 input signal to the transmitter unit 2 switched on, a ‘watchdog’ signal is also periodically, preferably every thirty seconds, sent to the receiver unit 4; the receiver unit 4 will switch its switching live out 12 output signal off if it does not receive a watchdog signal within one minute of receiving the last watchdog signal, or an OFF command is received.

As noted above and with reference also to Figure 8, in another embodiment, the radio power switching system may comprise more than one transmitter unit 2 paired to a single receiver unit 4. In this way, a many to one remote switching network is created. The transmitter units (2a,2b) are both paired to the receiver unit 4 in the manor previously described. With both transmitter unit’s (2a,2b) switching live in (8a,8b) signals switched off, the switching live out 12 at the receiver unit 12 remains off. When either of the transmitter unit’s (8a’,8b’) switching live in (8a’,8b’) signals are switched on, the switching live out 12’ of the receiver unit 4’ will be switched on. The switching live out 12’ of the receiver unit 4’ will only be switched off when all of the other switching live in signals of the transmitter units are switched off or a watchdog signal is not received, as mentioned above.

In this way, the present invention can be used in conjunction with an underfloor heating system by replacing the switching live cable typically required between the zone valves and heat pump of the underfloor heating system. Each transmitter unit 2 would be coupled with a zone valve and be responsible for the temperature control of an individual room. Here, when a thermostat requests heat to a particular room, a voltage is applied to a solenoid coupled to the zone valve causing it to become ‘open’. At the same time, as the transmitter unit 2 is coupled with this same zone valve, a switching live in 8 input signal is now provided to the transmitter unit 2 which transmits a radio signal 5 to the receiver unit 4 which is coupled to the heat pump of the underfloor heating system. The switching live out 12 at the receiver unit 4 now becomes switched on and the heat pump turns on, circulating hot water towards the zone valve, and therefore, into the room that requested heating.

By using multiple transmitter units 2, for each of the Zone Valves of an underfloor heating system, paired to one receiver unit for the heat pump, dynamic and efficient control of a home’s underfloor heating can be achieved using the present invention without the need to implement complex, time consuming and expensive live switching cables between each room and the heat pump of an underfloor heating system. Additional transmitter units are erased using the magnet 14 with the receiver unit 4 in the same manner as described above to erase all previously paired transmitter units.

With reference to Figures 9 and 10, in another embodiment, the radio power switching system has been modified to allow the transceiver unit 3 to be used as both a transmitter unit 2 and a receiver unit 4 allowing bi-directional communication between the two paired transceiver units 3; Figure 9 shows front 3b and rear 3c views of the hardware of the unit 3a. Each transceiver unit 3 is identical and typically comprises power supply circuitry 16, a low voltage microcontroller control circuit 18, an RF transceiver 20 with an integral antenna 21, indicator LEDs 22, a reed switch 26, relay 28 changeover contacts and unit screw terminals 24 for voltage input and output connections to the surrounding unit circuity, with this circuitry functioning in a similar manner to the previously described receiver unit 4. Here, the indicator LEDs 22 provide illumination to give information on the status of the connection between paired transceiver units, but also, illuminate when a signal is both transmitted and received.

The power supply circuitry 16 is designed to allow adequate power to remain available for the transceiver unit 3 to transmit the OFF command several times over after the main power supply to the transmitting transceiver unit 3 has been removed.

With reference to Figure 11, the switched live cable 6a is connected to the cable gland 7a allowing the switching live in 8 and switching live out 12 to be connected to the unit screw terminals 24a. The permanent supply cable 6b is connected to the cable gland 7b and allows the permanent live 9 and neutral 10 connections to be made to the unit screw terminals 24b. The transceiver units can be paired together using a magnet 14 in close proximity to the reed switch 26 of the unit 3 in the same way as described above with these units being erased also in the same manner as described above.

Here, the various input and output connections required for the operation of the transceiver unit 3 have been simplified in the same manner as described above for the transmitter unit 2 and receiver unit 4 with an extra node, two for each unit, requiring connection. These transceiver units 3 may also be pre-paired in the same way as described previously, further contributing to the simplicity of installing these devices with the user’s desired electrical apparatus.

In this way, the present invention may be used in conjunction with a boiler system to aid in the replacement of older boiler models by removing the need to install a switching live cable required between the boiler and external water pump. The operation of this embodiment of the present invention will now be explained using an application example of a central heating system.

With reference to Figure 12, one transceiver unit 3 is connected to a boiler 28 and the other transceiver unit is connected to an external water pump 30. A standard three core mains supply line 29a is connected to both the boiler 28 and the transceiver unit 3 which typically comprises a permanent live 9, neutral 10 and earth 11 connections. All three of these connections are made to boiler with only the permanent live 9 and neutral 10 connections made to the transceiver unit 3. The earth 11 connection is made to the metallic body of the boiler 28 for safety reasons known to those skilled in the art. The switching live in 8a and switching live out 12b connections are connected between the boiler 28 and transceiver unit 3 in same manner as described by Figure 11.

The other transceiver unit 3’ is connected to the external water pump 30, which may be located some distance away from the boiler. A mains supply line 29b proximate to the external water pump 30 is connected to the wiring centre screw terminals 25 providing access to the permanent live 9, neutral 10 and earth 11 connections. The transceiver unit 3’ is connected to the permanent live 9 and neutral 10 connections in the same way as the unit 3; the switching live out 12a is connected between the transceiver unit 3’ and the external water pump 20, with the switching live in 8b connected to the wiring centre screw terminal 25 providing potential access to this particular connection by the rest of the system surrounding the terminal 25.

Both the room thermostat 32a and cylinder thermostat 34a are connected to the transceiver unit 3’ via the wiring centre screw terminal 25. Here, both the room thermostat output 33 and cylinder thermostat output 35 connect to the screw terminal 25 where the switching live in 8b is connected allowing both thermostats to drive the switching live in 8b input signal when required. The room thermostat output 33 first connects to the mid position valve 36 before subsequently connecting to the wiring centre screw terminal 25.

The programmer 38 is connected to both the permanent live 9 and neutral 10 connections and is individually connected, via switches (40b,42b), to the room thermostat 32a and cylinder thermostat 34a allowing for control over these parts of the system by way of a user interface on the programmer 38. When the central heating switch 40b of the central heating output 40a is closed, by the programmer 38 from the input of a user, the room thermostat switch 32b is closed, subsequently driving the switching live in 8b signal to the transceiver unit 3’. In the same way, the direct hot water output 42a is able to drive the switching live in 8b signal when being prompted by the programmer 38. The user input to the programmer may be by way of setting a timer, or a direct ‘on’ command of the central heating output 40a and or the direct hot water output 42a. The thermostats (32a,34a) are also able to trigger their switches (32b,34b), and thus drive the switching live in 8b signal, by way of their own thermosensitive sensors which trigger the switches (32b,34b) when the required temperature of the air, for the room thermostat 32a, or water inside the cylinder, for the cylinder thermostat 34a, is not being met.

With the system configured in this way, bi-directional communication between the paired transceiver units (3,3’) can be achieved. When the boiler 28 has heated water sufficiently and requires the external pump 30 to subsequently pump the heated water around the central heating system, the switching live in 8a of the transceiver unit 3 is switched on, by the boiler 28, causing a radio signal with an ON’ command to be sent to the other transceiver unit 3’. This received ON’ command drives the switching live out 12a output causing the external water pump 30 to turn on and begin pumping water.

When either of the two thermostats (32a,34a) drive the switching live in 8b input of the transceiver unit 3’ high, a radio signal is now sent back to the first transceiver unit 3 at the boiler 28 which drives the switching live out 12b output high commanding the boiler 28 to switch on and start creating hot water. Here, as mentioned above, the room thermostat 32a and cylinder thermostat 34a have independent access and control of the boiler 28 allowing each thermostat to turn the boiler on when required.

As the room thermostat output 33 is connected to the switching live in 8b input of the transceiver unit 3’ via the mid position valve 36 as mentioned above, the room thermostat 32a is able to control the valve 36 to turn on the boiler 28 and direct hot water from the boiler 28 to be used either by the radiators, coupled to the central heating system, or be stored in the hot water cylinder, or both.

Advantageously, the boiler 28 is provided direct control of the external water pump 20 without needing to share a switching live input with the pump 20. For conventional older boilers, this caused both the boiler and water pump to either be both on or off resulting in the common problem known as ‘boiler overrun’ which can cause damage to the boiler as residual heat is not able to exit the boiler because the water pump switches off instantly with the boiler. Giving the boiler 28 a permanent mains supply 29a and direct control of the external water pump 30 with a separate means for switching the pump 30 on and off helps to overcome this problem.

For the replacement of older boilers, by using the present invention, no difficult, time consuming and expensive physical live switching cables need to be deployed between the boiler and distant water pump to replace an older boiler with a new one. A standard three core mains supply cable already available within a home or dwelling can be used to provide a boiler with a permanent power supply where, previously, this same supply would have been required to provide the switching live in for both the boiler and water pump simultaneously.

Claims

1. Apparatus for a radio power switching system comprising a controller, transmitter and receiver, wherein the transmitter and receiver are coupled to a controller and configured to establish a radio frequency channel; wherein the radio frequency channel is arranged to be controlled by the transmitter and receiver at either end of the channel; wherein the receiver is connected to a controller; wherein the controller is coupled to a switch to allow the switch to be stimulated to turn on a mains supply voltage; wherein a radio signal is transmitted along the radio frequency channel, from the transmitter to the receiver; and wherein the received radio signals are fed into the controller, prompting it to stimulate the switch.

2. Apparatus according to claim 1, wherein the controller, transmitter, receiver and switch are arranged to form part of an integral transceiver unit which is able to both transmit and receive radio signals.

3. Apparatus according to claim 2, wherein two of the transceiver unit of claim 2 are arranged to be paired together using a radio frequency connection to allow bidirectional communication between the transceiver units.

4. Apparatus according to claim 3, wherein the transceiver unit is arranged to have an input and an output connection terminal for the connection of a switching live signal and a mains supply voltage.

5. Apparatus according to claim 4, wherein the input and output connection terminal of the transceiver unit is arranged to be connected to via two cable glands, wherein each cable gland permits the connection of external electrical connections to the transceiver unit.

6. Apparatus according to claim 5, wherein a pair of transceiver units are pre-paired prior to the installation of the pair of transceiver units with electrical apparatus.

7. A system comprising two transceiver units as clamed in any of claims 2-6, wherein the system is for a central heating configuration; wherein the central heating configuration comprises a boiler and an external water pump; wherein the transceiver units are arranged to be paired together to establish a radio frequency connection to allow radio signals to be transmitted and received at both ends of the connection; wherein the switching live input and output terminals of the first transceiver unit are arranged to be connected to a boiler and the switching live input and output terminals of the second transceiver unit are arranged to be connected to an external water pump; and wherein the received radio signals are fed into a controller, prompting it to stimulate a switch to allow bi-directional control of the boiler and external water pump.

8. A system according to claim 9, wherein the central heating configuration further comprises a room thermostat and cylinder thermostat which are connected to the second transceiver unit’s switching live input terminal to allow the thermostats to also control the boiler.

9. A system according to claim 8, wherein the central heating configuration further comprises a programmer which is connected to the room thermostat and cylinder thermostat to allow user control of the thermostats from the programmer.

10. A system according to claim 9, wherein the user control of the boiler is in the form of setting a timer to control when the boiler is switched on and off.

11. Apparatus according to claim 1, wherein the transmitter and receiver form separate integral transmitter and receiver units which are able to transmit and receive radio signals respectively.

12. Apparatus according to claim 11, wherein the transmitter unit and receiver unit are arranged to be paired together using a radio frequency connection to allow unidirectional communication between the transmitter unit and the receiver unit.

13. Apparatus according to claim 12, wherein the transmitter unit comprises an input connection terminal for the connection of a switching live input signal.

14. Apparatus according to claim 12 or 13, wherein the receiver unit comprises an input and output connection terminal for the connection of a switching live output signal and a mains voltage supply.

15. Apparatus according to claim 14, wherein the input and output connection terminal of the transmitter unit is arranged to be connected to via a cable gland, wherein the cable gland permits the connection of external electrical connections to the transmitter unit.

16. Apparatus according to claim 14, wherein the input and output connection terminal of the receiver unit is arranged to be connected to via two cable glands, wherein each cable gland permits the connection of external electrical connections to the receiver unit.

17. Apparatus according to claim 15 and 16, wherein the pair of transmitter and receiver unit are pre-paired prior to the installation of the pair with electrical apparatus.

18. Apparatus according to claim 16 or 17, wherein multiple transmitter units are paired to the same receiver unit.

19. A system comprising a transmitter unit and receiver unit as claimed in any of claims 2 to 18, wherein the system is for an underfloor heating configuration; wherein the underfloor heating configuration comprises a thermostat, zone valve and heat pump; wherein the transmitter unit and receiver unit are arranged to be paired together to establish a radio frequency connection to allow radio signals to be transmitted and received at both ends of the connection; wherein the switching live input of the transmitter unit is arranged to be connected to a thermostat and the switching live output of the receiver unit is arranged to be connected to the heat pump; and wherein the received radio signals are fed into a controller, prompting it to stimulate a switch to allow uni-directional control of the heat pump from the thermostat.

20. A system according to claim 19, wherein multiple transmitter units are coupled with an equal number of thermostats, wherein each additional transmitter unit is able to be paired to the same receiver unit to allow each paired transmitter unit to control the heat pump.

21. Apparatus according to any of the preceding claims, wherein a reed switch is coupled to a controller and is arranged to be stimulated by a magnet; wherein the reed switch is arranged to output a signal to the controller upon being stimulated; wherein the controller interprets signals received from the reed switch to begin a pairing protocol between a receiver and a transmitter; and wherein the controller interprets additional signals received from the reed switch for the erasing of a paired transmitter and receiver.