EP3543446B1 - Wireless component of a fire resistant holding installation or a fire alarm system, method for displaying signal strength - Google Patents

Description

The invention relates to a wireless component of a fire protection detection system or a fire alarm system.

The US 2016/237732 A1 discloses a door locking system with a mechanically pre-stressed door closer which is arranged on a support surface on or next to a wing door. The system also includes a rotating door closer arm connected at one end to the door closer and at the other end configured to close the door. The door locking system comprises a relay switch which receives a closing signal from a fire detection device, the relay switch closing a circuit upon detection of the closing signal. Closing the circuit provides an electrical coupling between a battery and a voltage converter. The voltage converter increases the battery voltage and provides an increased output voltage for an electronic shock. In response, the electronic strike opens and releases the door closer, which closes the door.

Referring to Fig. 4 a locking system 100 is first described in general, as it is from the DE 102014225297 B4 is known. In Fig. 4 arrows describe radio links between boxes, while lines represent wired connections. 112 are two wireless fire sensors and 114 is a manual trigger button. Fire detectors can detect fire conditions such as smoke or certain gases and possibly also radiation and emit a corresponding alarm signal. The signal is emitted via the radio link shown. A qualitatively identical alarm can be triggered via a manual trigger button 114, which is also transmitted via a radio link.

A communication interface is designated by 126, which carries out radio communication with the peripheral radio components of wireless fire alarms 112 and manual trigger buttons 114 (hereinafter also referred to only as "peripheral components") enables. The communication interface 126 is also referred to as a "central component". The communication is preferably bidirectional. Then all components 112, 114 and 126 are sending and receiving.

A suitable multiplex can be implemented to handle the multiple channels. On the hardware side, it can be defined by switches. Access conflicts will hardly occur on the radio side, as the signaling times are very short compared to the cycle times (factor <10 ^-6 ). However, if an unlikely access conflict arises, suitable resending routines are implemented so that messages are not lost. The peripherally transmitting components Wireless fire alarms and manual release buttons can also send identification data, so that it can be recognized in the communication interface 126 which component the respective shipment comes from.

128 is a resistance simulation means by means of which fault situations can be simulated in one component, in particular a central component, which affect another radio component 112 and 114 (wireless components). “Component” can be understood to mean a system part that can be assembled or plugged in independently. A “radio component” or “wireless component” can be a component that sends and / or receives information from another component via a radio link. Wired components recognize their connection by means of resistance monitoring. Resistance very high or infinite or resistance very low or practically 0 mean a fault in the sense of a line interruption or a short circuit, while resistances in a medium range indicate a proper connection. This is checked by the monitoring component. So that a monitoring component can run the same monitoring routines for coupled radio components as for hardwired components, a resistance simulation means 128 is provided at the monitoring radio interface 126. If the signal exchange over the radio link at the radio interface 126 shows that there is a radio connectivity problem or some other problem in the coupled radio component, the resistance simulation means 128 (controlled by the radio interface or its own logic) can be used to signal this problem as a wire break or short circuit of a hardwired component would. The communication interface 126 and the resistance simulation means 128 can be combined to form an additional module 124. The additional module 124 is connected to a control and / or evaluation device 118 (hereinafter also referred to as controller 118 for short). The connection can be established by directly plugging in the module on the device 118 or by means of an elongated line. However, it is just as possible to provide the communication interface 126 and the resistance simulation means 128 integrally with the controller 118. 116 is a power supply for the hardwired components.

120 is a locking device with a release device. It triggers a mechanical measure in response to the presence of predetermined conditions. This is usually the initiation of a door closing or a gate closing. The measure takes place as planned when the wireless fire alarm 112 or the manual trigger button 114 has first transmitted a corresponding signal via the radio link to the communication interface 126, which forwards it at least to the controller 118 and which then takes the necessary steps.

In order to monitor the connectivity between the radio components 112 or 114 and the communication interface 126, in addition to the notification of alarms, regular or periodic communication is implemented between them. If it does not take place or does not take place as planned, appropriate measures are initiated. The regular communication over the radio links is designed in such a way that it is started periodically by the peripheral component of wireless fire alarm 112 or manual trigger button 114. A message (hereinafter referred to as “connection test message”) is then sent from the peripheral component to the communication interface 126, from which it is acknowledged backwards to the peripheral component (which is hereinafter referred to as “acknowledgment message”). The period of these tests is less than 100 seconds, preferably less than 80 or less than 70 seconds. It can be over 40 or over 50 seconds.

The connection test message itself lasts only a few milliseconds, the same applies to the acknowledgment message, which is sent back to the peripheral component after receipt of the connection test message. If the controller 118 does not provide the expected Connection test message is received in the intended time window, further measures are initiated, which can also include the request for human intervention. If, in turn, the peripheral component 112, 114 does not receive the expected acknowledgment message, further measures can also be taken here, such as retry of the connection test message, possibly with other parameters (higher transmission power), local or remote error notification and the like.

In many cases, the quality of the connection between peripheral components and central components also depends significantly on the installation conditions or installation conditions and installation locations of these components. Because of reflections, standing waves and the like, a few centimeters difference in the installation location of a radio component can actually cause very clear differences in the quality, in particular signal strength, of the signals received and possibly also the signals transmitted.

When assembling the components, care must therefore be taken to find a convenient installation location. However, other parameters can also be just as relevant as the installation location, such as the alignment of the radio-communicating component (in particular its antenna), possibly the choice of frequency, design of the surroundings of the radio-communicating components and the like.

The fitter is responsible for designing these parameters when assembling the components. So far, it has been very time-consuming to give the fitter suitable feedback for this. Sometimes the assembly takes place without feedback or "by feeling". In some configurations, two fitters are necessary, namely one on the component to be assembled and one on a central system, which possibly has information about signal strengths, the two fitters then having to communicate with one another. Or the fitter has to carry complex equipment that determines and outputs the values. However, the latter is only helpful to a limited extent, because in principle the equipment carried along cannot be at the location of the component to be assembled, because this location is already occupied by the component to be assembled.

The object of the invention is to specify a wireless component of a locking system or a fire alarm system that enables signal strengths to be displayed locally.

This object is achieved with the features of the independent patent claims. Dependent claims are directed to preferred embodiments of the invention.

A wireless component has a measuring device for measuring the signal strength of received waves. It also has an evaluation device that generates a signal strength value according to the output of the measuring device. Finally, it generates a signal corresponding to the generated signal strength value and sends it to an interface of an output device, the interface undertaking or enabling a local display of the signal strength value.

In this way, the fitter has a clue directly from the device as to how good the signal strength of received waves is.

The component is also designed to receive a signal strength value determined and transmitted by another wireless component and to output this received signal strength value together with the self-determined signal strength value locally in a distinguishable manner or to present it in a distinguishable manner.

The received signal strength value is in particular the signal strength that the remote wireless component measures on the shafts that it receives from the component to be assembled. It is assumed here that the component to be assembled already sends and receives signals as intended during assembly. In this way, the fitter then has an indication of the quality of the radio connection in the transmission direction as well as in the reception direction during assembly. He (or she) can then design installation conditions in accordance with these advertisements, so that a suitable arrangement can ultimately be found in a relatively simple manner. The local display can be a visual display or an acoustic display. Enabling a local display can also include generating suitable signals, which in turn can be tapped either wirelessly or via a plug connection on the component to be mounted and displayed in a separate device.

The generated signal strength value can be an average of several values measured in series. In this way, transient changes are averaged out, so that blatant incorrect determinations are less likely.

In addition to the local presentation of the signal strength value generated by the user’s own measurement, this can also be transmitted in a suitable manner to a remote wireless component in order to be available and evaluable there.

Finally, a selection device can be provided in order to switch on or off the local presentation / provision of signal strength values. Upstream components / measures can also be switched on or off, for example the operation of the evaluation device and the operation of the measuring device. Since wireless components often have a limited power supply (battery), it is desirable to keep unnecessary parts running as much as possible to reduce. Since the described presentation of the signal strengths is not required all the time, it is therefore desirable to be able to selectively switch on or switch off the associated parts in order to save energy.

The wireless component overall has a first radio interface for transmitting and / or receiving electromagnetic waves that transport energy and / or information to or from a remote component. This can include sending the messages described in relation to the prior art (connection test message, acknowledgment message, alarm message, fault message). The associated radio interface is bidirectional. In the wireless component to be installed, the signal strength of the received wave is measured at the bidirectional interface.

The wireless component can have a device for requesting or causing the temporary shortening of the period duration of the communication signals. For example, if the usual period is 60 seconds and five values are taken into account for averaging, it would take four minutes each to collect five values in order to test the quality of a particular assembly configuration. To shorten this period of time, it is desirable to shorten the period of the sending of the messages so that measured values are available more quickly. Accordingly, the peripheral component has a device for requesting or causing the temporary shortening of the period of the transmission of the communication signal.

The component can also be set up for communication with a third-party device and can have a communication connection for this purpose, which can be wired with a plug or wireless. The third-party device can carry out or initiate various interventions via such a communication connection, for example the aforementioned initiation of the shortening of the period duration, system reset, error and / or alarm simulation, requesting stored data and similar. However, the third-party device can also be used to present the determined and / or received signal strength value.

Generally speaking, the component is a peripheral component, in particular a fire sensor or a manual trigger switch, which is designed to send a detection signal or a manual trigger signal or a fault signal or an alarm signal to a central component via a first radio interface.

A method for presenting the signal strength of a radio signal received in a wireless component of a fire protection system has the steps of receiving electromagnetic waves that transport energy and / or information from a remote component, measuring the signal strength of the received waves, generating a signal strength value according to the measurement results, and outputting the signals corresponding to the generated signal strength value and a second signal strength value corresponding to a received signal strength value received from the remote component to a local display causing or enabling interface of the component.

A method for mounting a wireless component (10) of a fire protection locking system (1) has the steps of switching on the wireless component, displaying the signal strength of a radio signal received in the wireless component (10) as above, determining a mounting position according to the display, and mounting the component at the specified position.

Fig. 1

eine Komponente mit angekoppeltem System,

Fig. 2

die Vorgehensweise zur Erstellung eines Signalstärkewerts,

Fig. 3

das Aussenden von Kommunikationssignalen auf der Zeitachse, und

Fig. 4

eine bekannte Feststellanlage.

Individual embodiments of the invention are described below with reference to the drawings, as shown

Fig. 1

a component with a coupled system,

Fig. 2

the procedure for creating a signal strength value,

Fig. 3

the transmission of communication signals on the time axis, and

Fig. 4

a known locking system.

Fig. 1 Figure 10 shows a wireless component 10 and the system 2 through 6 to which it is coupled. The component 10 is preferably a peripheral component, that is to say in particular a fire sensor or a radio fall alarm or a manual release switch or a radio release device or a radio closing sequence control device or a radio door closer. However, it can also be a central component, for example a controller or a radio communication module or a radio energy supply. However, assuming that the in Fig. 1 The wireless component 10 shown is, for example, a fire sensor, it communicates via a radio link with a central radio communication module 6 of the locking system 1. This in turn is connected to a central controller 2, which can be wired to other fire sensors 3, manual release switches 4 and locking devices 5.

In the component 10, it is assumed that the communication with the central components takes place by means of a first interface 17a, which interacts with the module 6 in a suitable manner. The initially mentioned protocol consisting of a connection test message from the peripheral component to the central component and, in response to this, an acknowledgment message from the central component to the peripheral component can be implemented between the peripheral component 10 and the system 1 or its central components. It runs via the aforementioned first interface 17a, which is preferably designed to be bidirectional.

A sensor or actuator, which is connected to the controller 12, is denoted by 9. The sensor can be a fire sensor or - instead - a manual trigger button. An actuator can be a locking device.

The controller has a general controller 12b for timing and sequence control. It also has a control unit 12a for controlling the processes and sequences considered according to the invention.

The component 10 also has a second interface 17c, 14 to 16 which enables a local display.

Generally speaking, the interfaces are supplied with the necessary signals by the control unit 12a. There are also signal converters 18 (drivers) in order to generate suitable electrical signals for the respective interfaces in accordance with the data from the controller 12a. The interface 14 to 16, 17c that enables a local display can be an acoustic interface 14 or an optical interface 15 or a plug connection 16 or a wireless interface 17c. 13 symbolizes an energy supply. It can be a battery.

Reference numeral 11 denotes a device for measuring the signal strength of the received electromagnetic waves. Basically, it can always take measurements, while the control ensures that the output values are used in a suitable manner only during reception and not during transmission. If the output transmission power is of interest, this can then also be evaluated by control intervention. Generally speaking, the evaluation device 12a receives the outputs of the measuring device 11 and uses them to determine a signal strength value. Many of the processes can be implemented digitally, so that the output of the measuring device 11 is converted into digital and can be further processed in this way. However, analog processing is also conceivable.

If a suitable signal strength value is present, the controller 12 generates suitable signals for an interface that enables a local presentation and delivers them to this interface. It should be noted that in real devices the locally acting interfaces are not as in Fig. 1 shown must be present in parallel. They can have a wireless interface 17c or an optical interface 15 or an acoustic interface 14 or a plug interface 16.

The signal representing the signal strength value is displayed or at least made accessible via the second interface 14 to 16, 17c that enables the local presentation, so that its local presentation occurs or becomes possible. In this way it is then possible for a fitter to be able to recognize the reception quality directly on site and possibly directly on the device, so that he can adjust his installation measures accordingly.

Furthermore, the controller 12 can be designed to generate a signal for the first interface 17a to the central unit for the signal strength value based on the local measurements, so that the central unit is also informed of the signal strength at the reception of the radio component 10.

In contrast to this, the remote wirelessly coupled radio module 6 can, for example, measure the signal strength received from the component 10 and send this value as a signal strength value to the component 10 via the first interface 17a. Assuming that the generation of the signal strength value for the received waves takes place in a first subdevice 12a1, a signal for the second interface 14 to 16, 17c is generated in a second subdevice 12a2 from the value received via radio, so that the so received Signal strength value can be presented locally. In this way, it is possible to present both the signal strength at the reception of the peripheral component and the reception signal strength delivered by the local component 10 locally at the receiving component (for example at the module 6). The presentation of these two values takes place in a suitably distinguishable manner, for example alternately or in parallel, if appropriate output devices are provided for this.

An optical local interface can work with luminosity as a measure of the signal strength value or with a bar diagram consisting of several light-emitting diodes or it can have a small LCD display on which a bar diagram can also be presented. An acoustic interface can provide a measure of the signal strength value to be displayed by means of frequency or volume. A plug interface 16 (for example USB) or a second radio interface 17c can interact with a local third-party device that is suitably set up. Such a third-party device can be a simple installation support device or can be configured up to a laptop or the like that is equipped with suitable software for evaluating the signals of the connector interface 16 or radio interface 17c (e.g. WLAN / WiFi, NFC, RFID, Bluetooth, DECT, ..) Is provided. In this respect, the component 10 can also have a general communication connection 16, 17c in order to be able to communicate with a third-party device. This communication connection 16, 17c can be formed by the already mentioned second radio interface 17c or plug interface 16 or by yet another radio interface 17b, for example WiFi / WLAN or NFC or Bluetooth. The third-party device can then initiate certain events in the component or via the component 10 in the central unit 2.

The signal strength value is preferably determined as the mean value of several measured values in order to be able to average out incorrect detections or transient disturbances. The signal strengths are preferably here periodically according to the protocol connection test messages and acknowledgment messages taking place. Since these are very short themselves (a few milliseconds), only one measured value can be generated per message. Since several periods are advantageously used for averaging, this means that several periods have to be waited for. If the period duration is comparatively long (for example over 30 seconds or over 40 seconds or over 50 seconds), this can mean that it is necessary to wait a long time until the appropriate number of individual values is available for averaging. Since this would have to be awaited for each individual attempted assembly variant, this is a very time-consuming and practically impossible process. According to one option, the component 10 is therefore equipped with a device which temporarily causes the protocol-compliant messages to be sent out with a shorter period. If the acknowledgment messages then arrive correspondingly at shorter periods, it is only necessary to wait for the sum of the shorter period, not for the longer period.

Fig. 2 shows the procedure or method for presenting the signal strength. In step 21, the signal strength of the signals received when a message is received is measured. This can lead to analog or digital values. The measurement takes place several times, and the several values obtained in this way are suitably processed in step 22 to form a signal strength value, for example offset to form an average value.

The signal strength value can be expressed in dB as the relative ratio of a received power to the transmit power or in absolute dBm as a received power in milliwatts or as SNR (signal-to-noise ratio), possibly also in dB, or as RSSI according to IEEE 802.11, and can be used in this Scaling are output.

Before step 21 of the measurement there can be a step (not shown) of causing a shorter period duration, as referring to FIG Fig. 3 described. After the averaging 22, further steps 23 can follow, for example resetting to normal period duration, and then sending the signal strength value obtained to a central component (step 24). In addition, the value is output to the second interface, which enables a local presentation, so that it is displayed locally or is available.

Fig. 3 shows the process on the time axis. The conventional period tp is, for example, 60 seconds. The periodic acknowledgment messages for the connection test message sent out by the peripheral component 10 then arrive at t = 0, 60, 120. It is assumed that at t = 170 seconds the period duration is reduced. A connection test message can then be sent from the peripheral component 10 to the central component 6/2, for example once per second, where its received field strength is measured (as explained above), so that a corresponding value is generated there that is the return to the component 10 sent acknowledgment message is impressed.

At the same time, the peripheral component 10 can measure the received acknowledgment signal by means of the measuring device 11 itself for signal strength. In the example shown, ten incoming confirmation messages can then be measured within approximately 9 seconds, so that sufficient measured values are available for averaging within a comparatively short time. After a preset number of messages sent out, for example, it is possible to go back to the conventional period tp.

However, it is also conceivable, for example, to provide a switch or button (not shown) that a fitter can operate or hold down, and for as long as the switch is operated or pressed, connection test messages are sent out with the shorter period tk. When the switch is reset or released, the component 10 goes back to the normal period tp.

The period duration can be shortened to values so that the short period duration tk is less than 5 seconds or less than 2 seconds or less than 1 second or less than 0.5 seconds, but preferably greater than 0.05 seconds or 0.1 Second or 0.5 seconds.

The communication connection 16, 17c can also be used to shorten the period from tp to tk and also to go back to tp. If necessary, a system reset can also be initiated via the third-party device and the communication connection, or an error and / or alarm situation can be set or data that has been stored for a long time can be read out. In this respect, the component 10 can have a memory which stores values, for example a predetermined number of the last measured signal strengths or a recently determined signal strength value.

The controller 12 can also have a selection device or switching device 19 in order to determine whether the measurement of the incoming signal strength and any subsequent processing should be carried out or not. Peripheral components 10, insofar as they are connected via radio, often have limited energy resources. In Fig. 1 a battery 13 is indicated. With this type of component it is desirable to use energy sparingly so that unnecessary measures are avoided as far as possible. Since the measurement of the incoming signal strength is usually only required during the assembly of the component 10, it may be desirable to carry out the necessary processing (signal strength measurement, averaging, signaling, ...) only during assembly and to omit it afterwards. Accordingly, a switching device 19 can be provided in order to precisely this To be able to make a choice. It can be a mechanical switch or an electronic switch that is operated, for example, from a writable register. The switching device 19 can also be coupled to the switch or button to shorten the period as described above or can switch automatically by being "on" after the battery is inserted or the power supply is switched on and is set to "off" after a certain period of time .

If the locally acting interface 17c is a radio interface, it can be the same as the first interface 17a for interaction with the central module 16. The locally available third-party device is then designed to "listen" to the data exchange between the components 10, 6, 2 mentioned.

Generally speaking, the radio interfaces can implement known radio standards, such as WLAN / WiFi, Bluetooth, NFC, RFID, DECT or the like. The radio frequency between peripheral component 10 and control center (that is to say radio interface 17a) can be between 865 and 870 MHz, in particular 868 MHz.

Features in this description are to be viewed as combinable with one another even if their combination is not expressly described, insofar as it is technically possible. Features that are described in a certain context, claim, figure or embodiment are also to be understood as being removable therefrom and combinable with other contexts, claims, figures or embodiments, insofar as this is technically possible. Descriptions of process steps should also be understood as a description of components that implement these process steps, and vice versa.

List of reference symbols

1

Hold-open system, fire alarm system

2

central control

3

Fire alarm sensor

4th

Manual release button

5

Locking device

6th

Communication module

9

Sensor, actuator

10

component

11

Measuring device

12th

control

12a

Evaluation device

12a1

first partial device

12a2

second partial device

13th

power supply

14th

acoustic interface

15th

optical interface

16

Connector interface

17a, 17b, 17c

Radio interfaces

18th

Driver for the interfaces

19th

Dialing device

21-25

Procedural steps

100

Hold-open system

112

wireless fire detector

114

wireless manual release button

116

power supply

118

control

120

Locking device with release device

124

Additional module

126

Communication interface

128

Resistance simulation agent

Claims (15)

1. Wireless component (10) of a fire prevention door-retaining system (1), having
   a first radio interface (17a) for receiving electromagnetic waves that transport power and/or information from a remote component that receives the radio signal of the fire prevention door-retaining system,
   a measuring device (11) for measuring the signal strength of the received waves,
   an evaluation device (12a) that generates a signal strength value in accordance with the output from the measuring device, and
   an output device (14 - 17) having a second interface (14 - 16, 17c), which produces or allows a local display, for outputting a signal corresponding to the signal strength value via the second interface (14 - 16, 17c), characterized in that
   the evaluation device (12a) has multiple partial devices (12a1, 12a2), wherein a first partial device (12a1) is designed to generate a first signal strength value in accordance with the output from the measuring device (11), and wherein a second partial device (12a2) is designed to generate a second signal strength value in accordance with a received signal strength value received from the remote component, to accordingly generate independent signals and to output said signals via the second interface (14 - 16, 17c).
2. Wireless component (10) according to Claim 1, in which the second interface has an optical interface (15) and/or an acoustic interface (14).
3. Wireless component (10) according to Claim 1 or 2, in which the second interface has a second radio interface (17c) and/or a connector interface (16).
4. Wireless component (10) according to Claim 1 or 2, which is or has a fire detector or a radio drop detector or a manual trigger switch or a central controller or a radio communication module or a radio power supply apparatus or a radio trigger apparatus or a radio closure sequence control apparatus or a radio door closer.
5. Wireless component (10) according to one of the preceding claims, in which the evaluation device is designed to generate the signal strength value according to multiple single values ascertained serially in time, in particular as the mean value of said single values.
6. Wireless component (10) according to one of the preceding claims, in which the output device (14 - 17) has multiple interfaces (14, 15, 16, 17a, 17b, 17c) and is designed to also generate a signal for the first radio interface (17a) for a signal strength value and to output said signal to the first radio interface.
7. Wireless component (10) according to one of the preceding claims, having a switching device (19) for selectively connecting and/or disconnecting the use of the second interface and of possibly upstream signal generation components and partial devices.
8. Wireless component (10) according to one of the preceding claims, which is provided with a preferably bidirectional communication device for sending a repeatedly, preferably periodically, transmittable communication signal and for receiving a correspondingly periodically receivable confirmation signal, wherein the measuring device (11) is designed to generate a signal strength value for the strength of the waves of the received signal.
9. Wireless component (10) according to Claim 8, having a device for requesting or prompting the intermittent shortening of the period duration of the transmission of the communication signal.
10. Wireless component (10) according to one of the preceding claims, in which a controller (12) is connected to a communication connection (16, 17c) for the purpose of data interchange with a third-party device, wherein the controller (12) is designed to take data received from the third-party device via the communication connection as a basis for performing control actions in the component, in particular one or more of the following actions:

    • requesting or prompting the intermittent shortening of the period duration of the transmission of the communication signal according to Claim 9,

    • requesting or prompting a system reset,

    • requesting or prompting an error simulation and/or an alarm simulation,

    • requesting stored data.
11. Wireless component (10) according to one of the preceding claims, having a memory for storing one or more of the signal strength values, wherein the controller (12) is designed to output one or more of the stored signal strength values via the output device (14-17) in response to a predetermined condition.
12. Wireless component (10) according to one of the preceding claims, which is a fire detector having a fire sensor (11) or a manual trigger switch having a manual switch and which is designed to transmit a detection signal or a manual trigger signal or a fault signal to a receiving component (2, 6) via the first radio interface (17a) .
13. Wireless component (10) according to one of the preceding claims, in which the radio interface (17) is a WLAN interface or a Bluetooth interface or a DECT interface or an RFID interface or an NFC interface or a GSM interface.
14. Method for presenting the signal strength of a radio signal received in a wireless component (10) of a fire prevention door-retaining system (1), having the steps of
    receiving electromagnetic waves that transport power and/or information from a remote component that receives the radio signal of the fire prevention door-retaining system,
    measuring the signal strength of the received waves, generating a signal strength value in accordance with the measurement results, and
    outputting the signals corresponding to the generated signal strength value and to a second signal strength value in accordance with a received signal strength value received from the remote component to an interface (14 - 16, 17c) of the component that produces or allows a local display.
15. Method for installing a wireless component (10) of a fire prevention door-retaining system (1), having the steps of
    switching on the wireless component,
    presenting the signal strength of a radio signal received in the wireless component (10) according to Claim 14, determining an installation position according to the presentation, and installing the component at the determined installation position.

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