WIRELESS NETWORK ADDRESS ALLOCATION

Description

Field of invention

[0001] The invention relates to the assignment of network addresses to devices, such as fans, during system commissioning and, in particular, when replacing defective devices in a system. Furthermore, the invention relates to a system configured as a dynamically addressable master-slave system and a method for addressing the slave units in this system.

[0002] There are various methods for assigning addresses in a network, such as manual IP address assignment for network devices (computers, printers, etc.), serial number-based auto-addressing, address assignment according to a specific cable plan, or shift register address assignment. An automated addressing process is proposed, for example, in DE 103 36 301 A1. A bus-based addressing method for slave units is known from EP 2 287 689 EP.

[0003] From DE 29907265 U1 a data transmission device with a configuration device is known in which the serial number is obtained automatically.

[0004] Bus systems are used, for example, to transmit data between multiple participants in a plant network. Bus systems of various types have been known for a long time. The master / slave bus systems underlying the present invention typically have the characteristic that all slave units must have unique network addresses in order to be addressed individually. Using a bus system, individual slaves can thus be addressed individually and specifically, allowing the slaves' settings to be changed or status information to be queried from the slave.In a system where serial number-based devices, such as motors, fans, or other units with a serial number, are present, and where one or more defective devices need to be replaced, the replacement devices to be installed should identically adopt the logical addresses of the devices removed from the system, so that each new device is recognized by the network like the original device and has exactly the same logical network address that the device previously had at that system location.

[0005] This allows a master unit to actuate a system component controlled by a specific slave unit, and therefore, in the case of a replaced slave unit, to assign received messages to such a slave unit and thus to a very specific system component. To ensure such functionality, the replaced slave unit requires, firstly, a system component. Conventionally, this is achieved, for example, by performing an addressing or orientation phase during the initialization of a bus system. In this phase, system addresses are assigned to the slave units in a specific sequence, or the master unit is given the opportunity to query sequentially stored device identifiers from individual slave units at different positions.However, when replacing defective devices, this type of address assignment does not offer a solution to achieve the aforementioned goal: that each new device with a changed serial number is recognized by the network in the same way as the original device, which has a different serial number, and should have exactly the same logical network address, now with a different serial number, as the device previously located at this system position.

[0006] In German patent application DE 10 2014 117 797.5 A1, a master-slave system is proposed that is configured such that a signal (signal change) from a serial signal sequence, provided by the digital output, is detected at the input of the next slave unit. This signal increments the address of the corresponding slave unit by the value "1", stores the signal change in memory, and outputs a signal corresponding to the memory's contents. A disadvantage of this addressing method is that addressing via shift registers requires a clock signal from the master, thus preventing a connection to the serial number. While a replaced device receives the address defined in the slave unit series, the master unit and central control system have no way of knowing which specific device with which serial number was installed or replaced.If several such replacement measures take place over time, the data in the system will no longer match the serial numbers at the time of commissioning.

[0007] A different method is disclosed in US patent 8,856,413 B2, comprising an interface bus, an enable circuit with a switch, and two control terminals connected via the enable circuit. The system is configured so that address assignment is only possible when the bus interface control signal is present at one of the terminals and the signal switch is open to control the enable function. Otherwise, the enable circuit locks the slave unit. A disadvantage of this method is that it also fails to solve the previously described problem of device replacement.

[0008] WO 2013 / 107704 A1 stipulates that a server assigns an identifier to a field device based on a data set which includes position and unique identifier, and uses this identifier for communication.

[0009] Against this background, the object of the present invention is to at least partially reduce the aforementioned disadvantages and to provide an improved method for addressing slave units in a plant network.

[0010] This problem is solved by a method having the features of claim 1 and a device having the features of claim 11. According to the invention, a method for addressing one or more exchanged slave units in a master-slave system is provided, comprising a master unit and a plurality of slave units, wherein the slave units have both a unique serial number and a fixed network address and are connected to the master unit via a data communication system, and wherein a data assignment table is provided in a system memory of the master unit, in which the respective network addresses of the slave units are assigned to the respective serial numbers of these slave units according to their position in the system in a defined order, with the following steps: a. Recording the serial numbers of the slave units to be replaced; b. Input or transmission of the serial numbers of the replaced slave unit to the master unit in the order of recording; c. Replacing the serial number stored for the respective positions with the serial number entered for the newly installed slave unit and assigning it to the network address for this position in the data assignment table.

[0011] Within the scope of the present invention, "replacement device", "replaced device" and "replaced slave unit" each refer to the slave unit that was newly installed in the system as a replacement for the defective or removed device or slave unit.

[0012] The previous serial number can be replaced in the data mapping table by overwriting it with the serial number of the replaced (i.e., newly installed) device. Alternatively or additionally, the old serial number can be written to an archive, allowing hardware changes to the slave units to be tracked over a period of time.

[0013] In a preferred embodiment of the invention, the serial numbers of the replaced slave units are recorded by means of camera technology, preferably by photographing the nameplates of the respective slave units. This allows, for example, a service technician to remove defective fans from an air handling system and photograph the nameplates of the newly installed fans (slave units) in sequential numbering order. The system was originally configured with logical network addresses in a sequential order and should be restored to this order after the problem is resolved.

[0014] According to the invention, it is advantageously provided that the serial numbers are entered in the form of a serial number list in the order of the replaced slave units. Due to the identical recording sequence, the specific sequence of the new device serial numbers is also known, as is their position, since this corresponds to the position of the failed or removed devices. The recorded new serial numbers are transmitted to the system controller, preferably the master unit, in the recording sequence.

[0015] The input in the aforementioned step b) can advantageously also be done manually using an input mask, e.g. by keyboard input.

[0016] According to the invention, the transmission to the master unit can be carried out in different ways. The input and / or transmission in step b) can be performed automatically by means of a wired data transmission of the serial numbers to the master unit. In an advantageous embodiment, an interface can be provided for this purpose, such as a USB, Ethernet, RS485 or other suitable system interface, via which the serial numbers of the exchanged slave unit are entered in the sequence of acquisition.

[0017] Alternatively, the input in step b) can be performed automatically by means of wireless data transmission, preferably radio-based, acoustic, or optical transmission of the serial numbers to the master unit. For this purpose, it is advantageous to store the serial number of the respective slave unit on an RFID chip, preferably located directly on or within a housing of the slave unit being replaced, which is designed for radio transmission.

[0018] As an alternative to photographing or capturing the nameplate with a camera and performing an optical evaluation, another embodiment of the invention may provide that the necessary information is also stored in an RFID chip in the device, whereby the terminal box cover is preferably suitable, which, however, must remain firmly attached to the device.

[0019] Depending on the housing material, a functioning data transmission system must be ensured. With a plastic cover, it can remain in place during reading; with a metal cover, it must first be removed to prevent interference with the radio signal to the RFID tag due to the shielding effect of the metal cover. Reading can be performed with a mobile RFID-enabled device, such as a suitable smartphone with an app. In an alternative embodiment of the invention, the RFID tag can also be permanently integrated into the nameplate.

[0020] For address assignment, it must also be taken into account that each slave unit to be integrated into the network requires an individual access key, which, according to an advantageous embodiment of the invention, is directly derived from its serial number and can therefore be determined from the serial number photographed, captured via RFID, or otherwise recorded. For this purpose, the invention proposes that each slave unit possesses a network access key derived from its serial number.

[0021] In another preferred embodiment of the invention, it is provided that the master unit assigns the network address corresponding in the data assignment table to the respective replaced (exchanged) slave unit and preferably communicates with the corresponding slave unit via this address.

[0022] Another aspect of the present invention relates, in addition to the method, to a master-slave system comprising a master unit and a plurality of slave units, wherein each slave unit has both a unique serial number and a fixed network address and is connected to the master unit via a data communication system, and wherein a data assignment table is provided in a system memory of the master unit, in which the respective network addresses of the slave units are assigned to the respective serial numbers of these slave units according to their position in the system in a defined order.furthermore, input means are provided for entering a serial number of exchanged slave units or a list of such serial numbers, and a data exchange module for manually or automatically replacing the serial numbers stored via the input means for the exchanged slave units and for assigning them to the network address for this position in the data assignment table.

[0023] Other advantageous embodiments of the invention are characterized in the dependent claims or are described in more detail below together with the description of the preferred embodiment of the invention with reference to the figures.

[0024] They show: Fig. 1 a schematic representation of an exemplary embodiment of a master-slave system in a state after commissioning; Fig. 2 a schematic representation of the master-slave system according to Figure 1where the slave units (S2 and S7) have failed; Fig. 3 a schematic representation of the master-slave system according to the Figures 1 and 2 in which the failed slave units (S2 and S7) were removed and Fig. 4 a schematic representation of the master-slave system in which the failed slave units (S2 and S7) were replaced by new (replaced) slave units.

[0025] The invention is described below using an exemplary embodiment with reference to the Figures 1 to 4 described in more detail, whereby identical reference symbols indicate identical functional and / or structural features.

[0026] In the Figure 1Figure 1 shows a schematic representation of an exemplary embodiment of a master-slave system 100. The master-slave system 100 comprises a master unit 1 (central control) and slave units Si, wherein in this embodiment with i=8, eight exemplary fans are provided as slave units S1,..., S8.

[0027] Each slave unit Si has both a unique serial number Sni and a fixed network address Ai, here designated as A1,..., A8 in the example. The slave units Si are interconnected with the master unit 1 via a data communication system 3.

[0028] Furthermore, a data allocation table (A1, Sn1), (A2, Sn2), ... , (Ai, Sni) is provided in a system memory of the master unit 1, in which the respective network addresses Ai of the slave units Si are assigned to the respective serial numbers Sni of these slave units Si according to their position in a defined order in the system.

[0029] Furthermore, input devices 20 are available for entering the serial numbers Sni for the two fans S2 and S7 to be installed. In the Figure 2 Two replacement fans are shown as examples, which are also labelled with the reference numbers S2 and S7, as these are to be integrated into the system in the same order and are to receive the network addresses of the previous fans.

[0030] In this state, the two replacement fans S2 and S7 represent slave units that do not yet have a network address. Fig. 3This is a schematic representation of the master-slave system 100 according to the Figures 1 and 2 shown, in which the failed slave units S2 and S7 were removed and in the Fig. 4 A schematic representation of the master-slave system 100 is shown, in which the failed slave units were replaced by new (exchanged) slave units S2 and S7. According to the serial number acquisition sequence, each unit is assigned a unique position in the system, allowing the corresponding network address to be assigned via the acquisition sequence in the data assignment table. Furthermore, input devices 20 are provided for entering the serial numbers Sni, and a data exchange module 30 is provided for manually or automatically replacing the serial numbers Sni stored via the input device.

[0031] According to the invention, a number of variants are conceivable, which utilize the presented solution even in fundamentally different designs. For example, the method of recording the serial numbers Sni of the exchanged slave units can be carried out in another suitable way, in particular via RFID tags or via other electronic storage media that can be transmitted to the master 1 via an interface.

Claims

1. Method for addressing two or more replaced slave units (S1, ..., Si) in a master-slave system (100) comprising a master unit (1) and a plurality of slave units (Si), wherein the slave units (Si) have both a unique serial number (Sni) and a fixed network address (Ai) and are interconnected with the master unit (1) via a data communication system (3) and wherein a data assignment table ((A1, Sn1), (A2, Sn2), ... , (Ai, Sni)) is provided in a system memory of the master unit (1), in which table the respective network addresses (Ai) of the slave units (Si) are assigned to the respective serial numbers (Sni) of these slave units (Si) according to the position (i) thereof in a determined order in the system, said method having the following steps: a. acquiring the serial numbers (Sni) of the slave units (Si) to be replaced; b. inputting the serial numbers (Sni) of the replaced slave unit (Si) in acquisition sequence at the master unit (1); c. replacing the serial number (Sni) for the slave unit (Si), stored for the position (i), with the input serial number (Sni) and assigning it to the network address (Ai) for this position in the data assignment table ((A1, Sn1), (A2, Sn2), ... , (Ai, Sni)).

2. Method according to Claim 1, characterized in that the serial numbers (Sni) of the slave units (Si) to be replaced are produced by means of optical acquisition, preferably by means of photographic acquisition of the serial number of a nameplate of the respective slave unit (Si).

3. Method according to Claim 1 or 2, characterized in that the input of the serial numbers (Sni) is performed in the form of a serial number list of the slave units (Si) to be replaced in the sequence of the replaced slave units (Si).

4. Method according to any one of Claims 1 to 3, characterized in that the input in step b) is performed manually by means of an input mask.

5. Method according to any one of Claims 1 to 3, characterized in that the input in step b) is performed automatically by means of a wired data transmission of the serial numbers (Sni) to the master unit (1).

6. Method according to Claim 5, characterized in that the input in step b) is performed via an interface, such as a USB, ethernet, RS485, or another interface.

7. Method according to any one of Claims 1 to 3, characterized in that the input in step b) is performed automatically by means of a wireless data transmission, preferably a radio-based, acoustic, or optical transmission of the serial numbers (Sni) to the master unit (1).

8. Method according to Claim 7, characterized in that the serial number (Sni) of the slave unit (Si) is stored for the case of a radio transmission to the master unit (1) on an RFID chip, which is preferably arranged directly on or inside a housing of the respective replaced slave unit (Si) that is suitably designed for the radio transmission.

9. Method according to Claim 8, characterized in that each slave unit (Si) has a network access key derived from the serial number (Sni).

10. Method according to any one of the preceding claims, characterized in that the master unit (1) assigns the replaced slave unit (Si) the corresponding network address (Ai) from the data assignment table ((A1, Sn1), (A2, Sn2), ..., (Ai, Sni)) and preferably communicates via this with the corresponding slave unit (Si).

11. Master-slave system (100) comprising a master unit (1) and a plurality of slave units (Si), wherein every slave unit (Si) has both a unique serial number (Si) and a fixed network address (Ai) and is interconnected with the master unit (1) via a data communication system (3) and wherein a data assignment table ((A1, Sn1), (A2, Sn2), ... , (Ai, Sni)) is provided in a system memory of the master unit (1), in which table the respective network addresses (Ai) of the slave units (Si) are assigned to the respective serial numbers (Sni) of these slave units (Si) according to the position (i) thereof in a determined order in the system, wherein furthermore, input means (20) for inputting in acquisition sequence a list of two or more serial numbers (Sni) of replaced slave units (Si) in the system and a data exchange module for manually or automatically replacing the serial number (Sni) stored via the input means for the replaced slave units (Si) and for assigning it to the network address (Ai) for this position in the data assignment table ((A1, Sn1), (A2, Sn2), ... , (Ai, Sni)) are provided.