JP4129715B2 - HART device communication device used in distributed control system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention proposes a HART device communication apparatus used in a distributed control system (hereinafter referred to as DCS) that connects field devices (hereinafter referred to as HART devices) proposed by the HART (Highway Addressable Remote Transducer) Communication Association, and is proposed by the HART Communication Association. The present invention relates to an apparatus for communicating with a HART device via a DCS network by a commercially available tool (hereinafter referred to as a HART device tool) having a function of maintaining the HART device using a communication protocol.
[0002]
[Prior art]
Various HART devices proposed by the HART Communication Association as field devices are commercially available from various companies. The HART device communicates with the outside of the HART device by a signal (hereinafter referred to as a HART signal) in which a binary digital signal representing 0 and 1 at 1200 Hz and 2200 Hz is superimposed on an analog 4-20 mA signal that has been an industry standard for a long time. In this way, process values are exchanged and parameters are set from the HART device.
[0003]
In addition, HART device tools having functions for maintaining parameter settings of the HART device according to the communication protocol proposed by the HART Communication Association are available in various forms (tool applications for mobile terminals and PC platform operations). Is commercially available.
[0004]
Communication to the HART device by the HART device tool is executed via the HART modem, and between the HART device and the HART modem is executed by serial communication according to the RS-232C or RS-485 standard, and communication commands are standardized in the industry. The HART modem converts an RS-232C signal into a HART signal. The connection form operates as a primary master or secondary master proposed in the HART protocol.
[0005]
FIG. 7 shows the most basic 1: 1 connection form, where 1 is a HART device, 2 is a commercially available HART device tool, 3 is a HART modem, and 4 is an RS-232C cable. Such a simple connection form does not cause a communication problem.
[0006]
FIG. 8 is a network diagram showing a communication form when a plurality of HART devices are DCS field devices, which is a subject of the present invention. 1a, 1b,... 1n is a group of HART devices connected as field devices of the DCS 5, and communicates with the DCS via the interface means 6a, 6b,.
[0007]
Reference numeral 7 denotes a HART device maintenance network, which has a hierarchical structure with a plurality of multiplexer units 8 to 12 for guiding a commercially available HART device tool 2 to the interface units 6a, 6b,. The structure and scale of hierarchies differ depending on the number of HART devices handled and the development manufacturers.
[0008]
As described above, the network unique to the DCS 5 that communicates with the HART signal and the HART device maintenance network 7 are separate and independent. The HART device maintenance network 7 is implemented by an original design by a development manufacturer, and the communication protocol is different for each company.
[0009]
On the other hand, on the DCS5 side, even if it has a function of connecting a HART device, it does not have a function of connecting a HART device tool corresponding to the primary master or secondary master proposed in the HART communication protocol (HART device). DCS itself corresponds to a primary master or a secondary master), and the HART device maintenance network 7 must be a two-stand structure independent of the DCS network.
[0010]
[Problems to be solved by the invention]
Although the HART device tool 2 is connected to a kind of network system called DCS for process control, a completely different network 7 is constructed for maintenance of HART devices not related to process control. Must. For this reason, there is a problem that the cost of wiring, apparatus, and construction is wasted, and reliability is deteriorated due to the large number of wirings and apparatus.
[0011]
Further, when there is no maintenance network 7 or when it is desired to use another HART device tool that does not support the maintenance network 7, this HART device tool cannot be connected to the DCS 5. Therefore, it is inefficient to go to the place where the HART device is installed regardless of the application and purpose, or to remove the HART device at the relevant site and transport it to the place where the HART device tool is located and connect it directly to maintain it. There is sex.
[0012]
In order to solve such a problem, even if a DCS manufacturer intends to develop a HART device tool for DCS connection independently, the HART communication protocol is very flexible and functions unique to the HART device are freely provided. Depending on the calibration function, know-how specific to HART devices is required. For this reason, special development (maintenance) is required to support new HART devices (or revisions to HART devices) in the future. difficult.
[0013]
Against this background, the HART communication protocol is extremely flexible and difficult to develop unless it is a device manufacturer. In addition, if only the 4-20mA analog signal before the HART device is used, the process control will be used for the time being. Necessary process value is obtained. On the other hand, the setting and adjustment of the HART device can be performed independently of the process control, and does not necessarily require the DCS function for controlling the process control. For this reason, HART device tools have been developed independently on the HART device tool manufacturer side. Because of this background, there is currently no compatibility or affinity between the two.
[0014]
[Means for Solving the Problems]
In order to achieve such a problem, the invention according to claim 1 of the present invention is a distributed control system having a HART device in a field device.
Is connected to the network of the distributed control system, mapping and HART devices tool means to maintain the HART device according HART protocol corresponding to one-to-one communication over a HART modem, the address on the distributed control system and the HART protocol and a device selector means having a function of converting the protocol as well as to communicate with the device selector means and to display the HART equipment to be switched connection information to be selected by the user is acquired from the device selector unit, the user of the There is a device remote control means having a function of returning selection information to the device selector means, and a COM port driver means for interfacing the device remote control means and the HART device.
[0015]
The feature of the invention described in claim 2 is that
A first platform connected to the distributed control system via a network and realizing a device selector means; the HART device tool means connected to the first platform via a network and realized as software; and The device selector means and the pseudo COM port driver means comprise a second platform on which the device selector means and the pseudo COM port driver means are realized.
[0016]
The feature of the invention described in claim 3 is that
The HART device tool means, the device selector means, the device remote control means, and the pseudo COM port driver means are realized on the same platform, and this platform is connected to the distributed control system via a network. .
[0017]
The feature of the invention of claim 4 is that
The device selector unit, the device remote control unit, and the COM port driver unit are connected to the distributed control system via a network and are realized on the same platform, and the COM port driver unit is connected to the COM port driver unit via an RS232C cable. The HART device tool means is connected.
[0018]
The invention according to claim 5
A first platform is connected via the network to the distributed control system the device selector unit is realized, connected via a first platform and a network of this, the device remote control unit, a COM port driver means The HART device tool means is connected to the COM port driver means via an RS232C cable.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall conceptual diagram in which the present invention is applied to DCS, and an additional function 13 for realizing the apparatus of the present invention relays a commercially available HART device tool 1 directly to DCS 5. By applying the present invention, the conventional HART device maintenance network 7 described with reference to FIG. 8 becomes unnecessary.
[0020]
The basic elements and functions of the functions of the apparatus of the present invention will be described with reference to FIG. Reference numeral 14 denotes a virtual interface boundary. The upper dotted line block A shows the basic connection form shown in FIG. Hereinafter, it will be described that the form in which the HART device tool is directly connected to the DCS by applying the present invention device is equivalent to A.
[0021]
The additional function 13 of the present invention is formed across the interface boundary 14. On the DCS 5 side, 15 is a device management tool that communicates with the DCS 5, and has a device selector means 16. Reference numeral 17 denotes a device remote control means formed on the HART device tool 1 side.
[0022]
The device selector means 16 has a function of selecting the HART device 1 on the DCS 5, a function of mapping addresses on the DCS and the HART protocol, and a function of converting the protocol. Via the device remote control means 17 on the HART device tool 1 side.
[0023]
The device remote control means 17 obtains DCS information for selection by the user from the device selector means 16 for display and selection by the user in order to switch which part of the HART device 1 on the DCS 5 is connected to. And a function of transmitting a result selected by this to the device selector means 16, and a function of handling a HART communication command between the device selector means and the RS232C port driver or pseudo driver (not shown).
[0024]
In FIG. 7, the HART device tool 2 has been described as an example in which a hardware-independent form is connected to a HART modem using an RS-232C cable. However, the HART device tool 2 is realized in software in an application space in a personal computer (PC). It is possible to use it in the same way. In this case, the device remote controller and the HART device tool are connected via a pseudo COM port driver formed in the kernel space in the PC.
[0025]
An embodiment in the case where the device of the present invention is specifically realized will be described below with reference to FIGS. The embodiment of FIG. 3 is an example of a two-platform type in which a platform P1 having device selector means 16 and a platform P2 having device remote control means 17 are connected by a network 18.
[0026]
The architecture of each platform includes hardware L1, kernel space L2, and application space L3. The platform P2 is realized by a PC, and the HART device tool 1 is configured in software in the application space L3 together with the device remote control means 17.
[0027]
The device selector 16 and the device remote controller 17 communicate via the network 18 by network drivers 19 and 20 that interface the application space and kernel space in each platform.
[0028]
In the platform P1, the device management tool 15 communicates with the DCS via a control bus indicated by VLnet via an application space communication library, a kernel space driver, and an adapter.
In the platform P2, the HART device tool 1 and the device remote control means 17 communicate via a pseudo COM port driver 19 formed in the kernel space.
[0029]
Next, an operation procedure in such a configuration will be described.
(1) The device remote control means 17 requests the device selector means 16 for DCS device connection information.
(2) In response to (1), the device selector means 16 returns the DCS device connection information to the device remote control means 17.
(3) Upon receiving the DCS device connection information according to (2), the device remote controller 17 displays the DCS device connection information on the screen and waits for which device the operator selects.
[0030]
(4) The device remote control means 17 sends the device selected by the operator to the device selector means 16.
(5) According to (4), the device selector 16 associates the IO polling address included in the HART command sent from the device remote controller 17 with the device connection information of the DCS, and notifies the device remote controller 17 that the association has been completed. Notice.
(6) By means of (5), the device remote control means 17 knows that the connection has been completed and prepares to receive the HART command from the HART device tool 1.
[0031]
(7) The HART device tool 1 sends a HART command to the pseudo COM port driver 19.
(8) The pseudo COM port driver 19 sends the HART command (7) as it is to the device remote control means.
(9) According to (7), the device remote control means 17 sends the HART command to the device selector means 16 as it is.
[0032]
(10) By (9), the device selector means 16 converts the HART command into a form handled by the DCS based on the information linked to the DCS device connection information from the IO polling address included in the received HART command.
(11) Conversely, the device selector means 6 converts the response from the HART device sent via the DCS into a HART command according to the HART protocol and sends it to the device remote control means 17.
(12) By means of (11), the device remote control means 17 sends a HART command response to the pseudo COM port driver 19.
[0033]
(13) According to (12), the pseudo COM port driver 19 sends the HART command to the HART device tool 1 in a form equivalent to that received from the RS-232C.
(14) The procedure from (7) to (13) is repeated each time the HART device tool 1 sends a HART command to the pseudo COM port driver 19.
[0034]
The embodiment of FIG. 4 has a function for realizing the apparatus of the present invention in one platform P3 (implemented with a PC), and the operation is exactly the same as that of FIG. This configuration is effective when the DCS is relatively small, and maintenance of the HART device can be performed with a single PC arranged close to the DCS.
[0035]
In the embodiment of FIG. 5, the function of realizing the device of the present invention is provided in one platform P3 (implemented by a PC) as in FIG. 4, but the HART device tool 1 is portable. It is suitable for realization. That is, the HART device tool 1 has an independent configuration as hardware as in the case of FIG. 7, is connected to the COM port 21 of the P3 by the RS-232C cable 4, and is further connected to the device remote controller via the COM port driver 22 in the kernel space. Communicate with means 17.
[0036]
Further, in this embodiment, the device selector means 16 and the device remote control means 17 are formed on the same platform, and thus communicate directly without going through the network driver. The illustrated network driver 23 is used as an interface for connecting the device management tool 15 to an external network.
[0037]
The embodiment of FIG. 6 is an example in which the platform is divided into two platforms as in FIG. 3, but the HART device tool 1 is provided by a tool independent of the platform P2 realized by the PC. It is a connection example. As in the case of FIG. 5, the connection is connected to the P2 COM port 21 via the RS-232C cable 4 and further communicates with the device remote control means 17 via the COM port driver 22 in the kernel space.
[0038]
【The invention's effect】
As is apparent from the above description, the present invention has the following effects.
(1) A HART device maintenance network (various devices and connection cables constituting them) becomes unnecessary.
(2) Remote operation is possible by directly connecting to the DCS.
(3) Any HART device tool that has a function to directly connect HART devices via RS-232C can be used regardless of application or manufacturer.
(4) When the HART device tool operates on the platform on the PC (FIGS. 3 and 4), the mapping function can be controlled on the same platform, and the design becomes easy.
[Brief description of the drawings]
FIG. 1 is an overall conceptual diagram in which the present invention is applied to a DCS.
FIG. 2 is a diagram for explaining basic elements and functions of a function of the device of the present invention.
FIG. 3 is a block diagram showing an example of a system that specifically implements the apparatus of the present invention.
FIG. 4 is a configuration diagram showing a second example of a system that specifically implements the apparatus of the present invention;
FIG. 5 is a configuration diagram showing a third example of a system that specifically implements the device of the present invention;
FIG. 6 is a block diagram showing a fourth example of a system that specifically implements the apparatus of the present invention.
FIG. 7 is a configuration diagram showing a basic 1: 1 connection configuration.
FIG. 8 is a network diagram showing a communication form when a plurality of HART devices are DCS field devices.
[Explanation of symbols]
1 HART device 2 HART device tool 4 RS-232C cable 5 DCS
13 Additional function 15 according to the present invention 15 Device management tool 16 Device selector means 17 Device remote control means

Claims (5)

In a HART device communication device used in a distributed control system having HART devices,
Is connected to the network of the distributed control system, a HART device tool means to maintain the HART device according HART protocol corresponding to one-to-one communication over a HART modem,
Device selector means having a function of mapping the distributed control system and the address on the HART protocol and converting the protocol;
Communicating with the device selector means and to display the HART equipment to be switched connection information to be selected by the user is acquired from the device selector unit, equipment remote controller having a function that returns the user selection information to the device selector means Means,
A HART device communication apparatus used in a distributed control system comprising this device remote control means and COM port driver means for interfacing with the HART device. A first platform connected to the distributed control system via a network and a device selector means realized, the HART device tool means connected to the first platform via a network and realized as software, and the The HART device communication apparatus used for the distributed control system according to claim 1, comprising a second platform on which device selector means and pseudo COM port driver means are realized. The HART device tool means, the device selector means, the device remote control means, and the pseudo COM port driver means are realized on the same platform, and the platform is connected to the distributed control system via a network. HART device communication device used for the distributed control system described. The device selector unit, the device remote control unit, and the COM port driver unit are connected to the distributed control system via a network and are realized on the same platform, and the COM port driver unit is connected to the COM port driver unit via an RS232C cable. The HART device communication apparatus used for the distributed control system according to claim 1, wherein the HART device tool means is connected. A first platform is connected via the network to the distributed control system the device selector unit is realized, connected via a first platform and a network of this, the device remote control unit, a COM port driver means A HART device communication apparatus for use in a distributed control system according to claim 1, wherein the HART device tool means is connected to the COM port driver means via an RS232C cable.

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