(19) United States
`(12) Patent Application Publication (10) Pub. No.: US 2003/0174070 A1
`(43) Pub. Date:
`Sep. 18, 2003
`Garrod et al.
`
`US 2003O174O70A1
`
`(54) WIRELESS SUPERVISORY CONTROLAND
`DATA ACQUISITION
`(76) Inventors: J. Kelly Garrod, Evergreen, CO (US);
`Timothy M. Sullivan, Littleton, CO
`(US)
`Correspondence Address:
`DORSEY & WHITNEY, LLP
`INTELLECTUAL PROPERTY DEPARTMENT
`370 SEVENTEENTH STREET
`SUTE 4700
`DENVER, CO 80202-5647 (US)
`(21) Appl. No.:
`10/389,341
`(22) Filed:
`Mar. 13, 2003
`Related U.S. Application Data
`(60) Provisional application No. 60/364,297, filed on Mar.
`13, 2002.
`
`Publication Classification
`
`(51) Int. Cl." ............................. H04Q 9/00; G08C 19/22
`(52) U.S. Cl. ......... 340/870.07; 340/825.69; 340/825.72
`
`(57)
`
`ABSTRACT
`
`A remote monitoring and control device or “remote device'
`generally for use in SCADA type environments. The remote
`device comprises a wireleSS IP type communication facility.
`The remote device further comprises a variety of commu
`nication channels, links, or ports for transmitting commands
`and receiving data to and from various instruments that may
`be connected with the remote device. Using the wireless IP
`communication facility, the remote device may provide a
`conduit for information and commands between the instru
`ments and a central computer. In addition, the remote device
`may monitor the instruments and provide an unsolicited
`communication with the central computer when an abnormal
`value is detected at an instrument.
`
`
`
`
`
`COPD Modem
`
`58
`
`RS232 three wire
`transceiver
`
`. . . .
`Serial Link
`
`- 60
`
`RS485 two Wire
`transCeiver
`
`Serial Link
`
`Emerson Exhibit 1019
`Emerson Electric v. Ollnova
`IPR2023-00626
`Page 00001
`
`

`

`Patent Application Publication Sep. 18, 2003 Sheet 1 of 4
`
`US 2003/0174070 A1
`
`Central Computer
`44
`sCADA client -
`
`OPC Sever
`
`42
`-1
`
`-
`
`- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
`
`46
`
`30
`
`40
`
`Y.
`
`-
`
`
`
`Monitoring Site
`(N)
`.
`
`-----
`
`Network
`
`
`
`Monitoring Site
`(O)
`
`FIG. 1
`
`IPR2023-00626 Page 00002
`
`

`

`Patent Application Publication Sep. 18, 2003 Sheet 2 of 4
`
`US 2003/0174070 A1
`
`- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
`
`38
`
`Remote
`Device
`
`36
`
`
`
`36
`
`
`
`
`
`
`
`Instrument (O)
`
`Programmable
`Logic
`Controller (0)
`
`Serial
`
`Instrument
`(N)
`
`
`
`
`
`
`
`Programmable
`Logic
`Controller (N)
`
`32
`
`36
`
`36
`
`34
`
`Monitoring Site
`(0)
`
`FIG. 2
`
`IPR2023-00626 Page 00003
`
`

`

`Patent Application Publication Sep. 18, 2003 Sheet 3 of 4
`
`US 2003/0174070 A1
`
`- 76
`?
`
`CXCOO
`
`- 32
`
`56
`
`78
`
`52
`N
`
`--
`
`COPD Modem
`
`UART
`
`58
`
`48
`
`50
`
`CPU
`
`
`
`Memory
`
`UART
`
`f
`
`62
`
`N
`UART
`RS232 three wire /serialik
`A
`transceiver
`64
`
`- 60
`66
`NJ
`RS485 two wire K serial link
`
`transCeiver
`
`--
`
`68-
`
`
`
`-- - - - - - - - -
`
`-
`
`- - - - - ----
`
`AVD
`
`Analog I/O
`
`/
`
`74-
`
`70
`
`I/O Pins
`|
`
`Digital I/O
`
`I/O Pins
`
`--- 72
`
`FIG. 3
`
`IPR2023-00626 Page 00004
`
`

`

`Patent Application Publication Sep. 18, 2003 Sheet 4 of 4
`
`US 2003/0174070 A1
`
`C start )
`
`MONITOR ONE OR MORE INSTRUMENTS
`
`GENERATE AN ALARMPACKET IF ONE OR
`MORE INSTRUMENTS HAVE A DATA VALUE
`MEETING OR EXCEEDING ONE OR MORE
`TRIGGER VALUES
`
`400
`-/
`
`410
`
`42O
`WIRELESSLY TRANSMIT THE ALARMPACKET -
`TO A CENTRAL COMPUTER
`
`
`
`430
`UPON RECEPT OF THE ALARMPACKETA
`THE CENTRAL COMPUTER, INITIATE APOLL OF -
`AT LEAST THE INSTRUMENT TRIGGERING THE
`ALARM
`
`WIRELESSLY TRANSMIT THE POLLDATA TO
`THE CENTRAL COMPUTER
`
`440
`
`
`
`
`
`
`
`c
`
`END
`
`S
`
`FIG. 4
`
`IPR2023-00626 Page 00005
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`

`

`US 2003/0174070 A1
`
`Sep. 18, 2003
`
`WIRELESS SUPERVISORY CONTROLAND DATA
`ACQUISITION
`
`CROSS REFERENCE TO RELATED
`APPLICATIONS
`0001. This application is a non-provisional application
`claiming priority to provisional application No. 60/364,297
`titled “Wireless Supervisory Control and Data Acquisition,”
`filed Mar. 13, 2002, the disclosure of which, including the
`appendix, is hereby incorporated by reference in its entirety.
`
`FIELD OF THE INVENTION
`0002 The present invention involves a wireless Supervi
`Sory control and data acquisition System, method, and appa
`ratuS.
`
`BACKGROUND
`0.003 Supervisory Control and Data Acquisition
`(“SCADA) involves the centralized control and monitoring
`of instruments and other equipment at remote locations. For
`example, a SCADA System may be employed at a pumping
`Station to monitor water level in tanks, pump operation,
`Valve States, and the like, and convey the information
`regarding all of the equipment to a central computer. More
`over, the SCADA System may be configured So that com
`mands may be issued from the central computer to activate
`or deactivate a pump, open or close a valve, and undertake
`any other actions at the remote location.
`0004 Conventional SCADA applications utilize a variety
`of technologies to retrieve data from remote locations.
`Oftentimes, conventional SCADA Systems require custom
`ized development of Sophisticated communication Systems
`in order to review information from remote locations. More
`over, conventional SCADA Systems typically require hard
`wire connections between instruments at the remote loca
`tions and centrally located monitoring facilities.
`0005 The technical advancement of cellular-type com
`munication infrastructure over the last Several years has
`increased the options available to communicate with remote
`locations. One advancement in the analog cellular infra
`structure is cellular digital packet data (“CDPD"), which
`provides a means of moving data within the cellular System.
`Similar technology has been developed for the digital wire
`less phone system. General packet radio service (“GPRS)
`provides data communications on the digital wireleSS phone
`system in a manner similar to CDPD on the analog cellular
`System. Generally, wireless type communication technology
`is continually evolving.
`
`SUMMARY OF THE INVENTION
`0006. One aspect of the present invention involves a
`remote monitoring and control device adapted to employ
`wireleSS data communication technologies, Such as the first
`generation cellular-based technology CDPD, the generation
`2.5 (“G2.5”) technologies GPRS, code-division multiple
`access (“CDMA') 1XRTT, and enhanced data GSM envi
`ronment (“EDGE”), and the generation three (“G3”) tech
`nologies wideband CDMA (“WCDMA") and CDMA
`3XRTT, and the like, in a SCADA application. A remote
`device employing wireleSS data communication technolo
`gies provides a simple and reliable communications link
`without the need to develop a large private communications
`
`network as in conventional SCADASystems. Another aspect
`of the present invention involves the use of a connectionless
`protocol for wireleSS data transportation between a remote
`device and a central computer.
`0007 Another aspect of the invention involves the real
`time monitoring of instruments at a remote location, and the
`notification of a central computer when a monitored instru
`ment exceeds Some threshold value. In this manner, the
`central computer or facility may be immediately notified
`when there is a potential problem at a remote location.
`0008 One aspect of the invention involves a remote
`monitoring device in communication with one or more
`instruments. The remote monitoring device comprises a
`central processing unit; at least one Serial port in commu
`nication with the central processing unit, the at least one
`Serial port for communicating with the one or more instru
`ments to receive data from the one or more instruments, and
`a wireleSS modem in communication with the central pro
`cessing unit, the wireleSS modem for transmitting the data
`from the remote monitoring device.
`0009. In one particular implementation, the at least one
`Serial port is for communicating with the one or more
`instruments to transmit and receive data to and from the one
`or more instruments, and the wireleSS data modem is for
`transmitting and receiving the data to and from the remote
`monitoring device.
`0010. The remote monitoring device may further com
`prise at least one input port and at least one output port in
`communication with the central processing unit. The at least
`one input port may comprise a plurality of analog inputs and
`a plurality of digital inputs, and the at least one output port
`may comprise a plurality of digital outputs and a plurality of
`analog outputs.
`0011. The wireless modem may comprise a cellular digi
`tal packet data modem, a general packet radio Service
`modem, a code-division multiple acceSS modem, an
`enhanced data GSM environment modem, a wideband code
`division multiple acceSS modem, and generally a wireleSS
`data communication technology processor. The wireleSS
`modem may be configured to transmit and receive data
`packets using a connectionless protocol Such as a user
`datagram protocol.
`0012 Another aspect of the invention involves a system
`for monitoring at least one instrument providing at least one
`data parameter. The System comprises a remote monitoring
`device including a wireless transceiver and at least one port
`in communication with the at least instrument, the at least
`one port receiving the data parameter from the instrument;
`a central computer in communication with the remote moni
`toring device; and wherein the remote monitoring device
`transmits a data packet associated with the at least one data
`parameter to the central computer using a connectionless
`protocol, Such as a user datagram protocol.
`0013 Another aspect of the invention involves a method
`for transmitting information from a remote location to a
`central location in a SCADA environment. The method
`comprises the operations of: monitoring one or more data
`parameters at the remote location; determining if the one or
`more data parameters meets a value; if the one or more
`parameters meets the value, generating at least one data
`packet indicative of the one or more data parameters meet
`
`IPR2023-00626 Page 00006
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`

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`
`Sep. 18, 2003
`
`ing the value; and wirelessly transmitting the at least one
`data packet to the central location.
`0.014. The operation of wirelessly transmitting the at least
`one data packet to the central location further may comprise
`employing a cellular digital packet data communication
`processor to wirelessly transmit the at least one data packet
`to the central location, employing a general packet radio
`Service communication processor to wirelessly transmit the
`at least one data packet to the central location, employing a
`code-division multiple access communication processor to
`wirelessly transmit the at least one data packet to the central
`location, employing an enhanced data GSM environment
`communication processor to wirelessly transmit the at least
`one data packet to the central location, employing a wide
`band code-division multiple access communication proces
`Sor to wirelessly transmit the at least one data packet to the
`central location, and generally employing a wireleSS data
`communication technology to wirelessly transmit the at least
`one data packet to the central location.
`0.015 The operation of wirelessly transmitting the at least
`one data packet to the central location may include using a
`connectionless protocol Such as a user datagram protocol.
`0016. The method may further comprise the operation of
`receiving a polling request from a central computer. The
`polling request may be generated at the central location in
`response to the receipt of the at least one data packet. The at
`least one data packet may comprise an alarm data packet.
`0.017. The method may further comprise the operations
`of retrieving the one or more data parameters; and wire
`lessly transmitting at least one Second data packet corre
`sponding with the one or more data parameters to the central
`location.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`0.018. The detailed description will refer to the following
`drawings, wherein like numerals refer to like elements, and
`wherein:
`0.019
`FIG. 1 is a system diagram illustrating a plurality
`of remote devices employed at various monitoring and
`control Sites, the remote devices in wireleSS communication
`with a network, and further illustrating a central computer in
`communication with the network, in accordance with one
`embodiment of the invention;
`0020 FIG. 2 is a system diagram illustrating a remote
`device employed at a monitoring site to monitor and control,
`directly or via wireleSS Signals from a central computer, a
`variety of instruments located at the monitoring Site, in
`accordance with one embodiment of the present invention;
`0021
`FIG. 3 is a block diagram of a remote device, in
`accordance with one embodiment of the present invention;
`and
`0022 FIG. 4 is a flowchart illustrating a method of
`monitoring one or more instruments, and generating at least
`one alarm if the one or more instruments goes out of range,
`in accordance with one embodiment of the present inven
`tion.
`
`DETAILED DESCRIPTION OF EMBODIMENTS
`OF THE INVENTION
`0023 Embodiments of the present invention involve a
`monitoring and control device with wireleSS communication
`
`capabilities (hereafter referred to as the “remote device”).
`The remote device is configured So that it may monitor,
`control, and generally provide a link through input and
`output channels to instruments that may be employed at any
`number of remotely located facilities. The remote device is
`further configured to wirelessly transmit and receive data,
`Such as data packets, corresponding with the monitored
`instruments and to and from a central computer upon receipt
`of a request from the central computer. Furthermore, the
`remote device may be configured to monitor its inputs and
`generate and transmit information, Such as an alarm data
`packet, to the central computer when the data received on an
`input channel indicates that Some instrument in the remote
`facility is out of range.
`0024 FIG. 1 is a system level diagram illustrating a
`central computer 30 adapted to communicate with one or
`more remote devices 32 employed at various remote loca
`tions 34, in accordance with one embodiment of the present
`invention. FIG. 2 is a second system level diagram illus
`trating one remote device 32 employed at a remote location
`34 to monitor and/or control various instruments 36 at the
`remote location 34 in accordance with one embodiment of
`the present invention. AS used herein, the term “remote
`instrument” or “instrument” will be used to refer to any type
`of instrument, Sensor, measurement device, programmable
`logic controller (“PLC), other remote device and the like,
`that may be employed at a monitoring location in a SCADA
`environment. AS used herein, the phrases “monitoring Site”
`or “monitoring locations' are used to refer to any location,
`facility, plant, treatment facility, processing facility, and the
`like where a System, method, or remote device conforming
`to the present invention may be employed to monitor and
`control instruments and equipment connected with the
`instruments.
`0025 The remote devices 32 are in wireless communi
`cation with a network 40, Such as the Internet, a wide area
`network (“WAN”), a local area network (“LAN”), or the
`like, by way of a wireless transceiver or transceivers 38
`operably connected with the remote device 32. One or more
`processing elements (hereafter the “central computer”) 30
`that are located at or away from the monitoring site are also
`in communication with the network 40. A System in accor
`dance with the present invention may be employed Such that
`remote devices 32 are geographically proximate the central
`computer 30 (e.g., physically located in an oil refinery) or
`may be geographically remote from the central computer 30
`(e.g., the central computer located at a facility in Texas and
`remote devices employed at oil fields in Colorado and
`Kuwait). Generally speaking, the remote device communi
`cates wirelessly with the central computer. The remote
`device may, however, be located closely to the central
`computer or quite far from the central computer.
`0026. One example of a remote monitoring site 34 that
`may employ Some or all aspects of the present invention is
`a water treatment facility. Typically, a water treatment
`facility has one or more Storage tanks. One parameter that
`might be monitored by a remote device 32 is the water level
`or Volume in each Storage tank. The water level in the
`Storage tanks can be used to determine water usage require
`ments for the region that the water treatment facility Supplies
`water to. The volume within the tank provides key infor
`mation for the plant operator to determine if the rate at which
`water is currently treated is consistent with usage throughout
`
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`

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`
`Sep. 18, 2003
`
`the System. For example, a high tank level indicates that
`more water is currently treated compared to usage. In
`contrast, a low tank level indicates that the usage is exceed
`ing treatment, and that treatment should be increased to
`avoid the tank completely emptying. In typical operations,
`the water level in large water Storage tanks does not exhibit
`dramatic fluctuations.
`0027. Another example of a remote monitoring site 34 is
`a water distribution infrastructure. The water distribution
`infrastructure typically includes pump Stations, lift Stations,
`preSSure reducing Stations and tanks, all of which have
`various parameters that require monitoring and have func
`tions that require control. In one example, it is important to
`monitor lift Stations since flooding may occur if the System
`is not operating properly. Additional examples can be found
`in the oil and gas industry to monitor and control well and
`pipeline instruments and equipment, and the electric utility
`industry to Signal and control potential problems on the
`distribution grid.
`0028. In a SCADA system employing a remote device, in
`accordance with the present invention, the remote instru
`ments are operably connected with devices, equipment,
`Storage tanks, pumps, and any number of other types of
`equipment that may be found at a remote monitoring site.
`For instance, in the above example of a water treatment
`facility monitoring location, a plurality of capacitive proX
`imity Sensor type instruments may be connected with the
`liquid Storage tanks in Such a manner as to detect various
`liquid levels in the tanks. A remote device conforming to the
`invention is operably connected with the capacitive proX
`imity Sensor. In general terms, a capacitive proximity Sensor
`reacts to the presence or approach of a target (e.g., water) by
`either providing a Zero Voltage at an output or by providing
`a Voltage at an output. The remote device detects the Voltage
`State of the proximity Sensor and Stores value in one or more
`registers of the remote device or generally in memory.
`0029 Generally, the remote device continuously or inter
`mittently monitors the State of each instrument connected
`with the remote device. Further, the remote device stores in
`memory, Such as one or more registers, at least the most
`recent information from the instruments. In response to a
`request or “poll” from the central computer, the remote
`device transmits a data packet corresponding with the infor
`mation from the monitored instruments to the one or more
`central monitoring computers. In the example above regard
`ing a connection of the remote device to capacitive proX
`imity Sensors, the remote device will transmit a data packet
`corresponding to the State of the Sensors and hence the
`central computer can determine whether the tank is full,
`empty, or at Some level therebetween. Besides transmitting
`data packets in response to a polling request from the central
`computer, the remote device may initiate the data packet
`transmission periodically, intermittently and/or in response
`to an unusual or alarm condition of the instrument or the
`mechanism that an instrument is connected with. In one
`particular implementation, the data packets from the remote
`device are wirelessly transmitted to the central computer
`using, in part, various wireleSS IP-type communication tech
`nologies, such as CDPD, GPRS, CDMA 1XRTT, EDGE,
`WCDMA, CDMA 3XRTT, and other wireless data commu
`nication technologies.
`0030) Referring to FIG. 1, in one particular implemen
`tation, the central computer 30 includes program code for
`
`executing a SCADA application package, Such as those
`provided by IconicsTM, RockwellTM, IntellutionTM, Wonder
`ware TM, and Wireless Systems T.M. In addition, the central
`computer 30 includes an OLE for Process ControlTM
`(“OPC”) server 42 in communication with the SCADA
`application 44. It should be recognized that the SCADA
`application 44 and the Server 42 may be run and/or imple
`mented on the same or Separate computing platforms. In one
`particular System implementation, the central computer 30
`has a unique IP address and is in communication with an
`Internet acceSS provider 46. The Internet access provider
`receives data packets, which have an internet protocol ("IP")
`destination address appended to the data packets corre
`sponding to the central computer address on the network,
`and routes the data packets to the central computer 30.
`0031. In one example, data packets are transported from
`the remote device 32 to the central computer based, in part,
`on the Modbus/TCP protocol as developed by Modicon/
`AEG Schneider AutomationTM. In contrast to the Modbus/
`TCP protocol, which uses the TCP/IP protocol, a remote
`device, System, or method of the present invention uses a
`connectionless protocol, Such as the user datagram protocol
`(“UDP). Since UDP is connectionless, the protocol avoids
`much of the overhead of the TCP connection establishment
`process. AS used herein, the term “connectionless” is meant
`to refer to network protocols and communication techniques
`in which one device may communicate with another device
`without first establishing communication with the other
`device. Although not preferable, a remote device of the
`present invention may also be implemented with the TCP/IP
`protocol.
`0032 FIG. 3 is a block diagram of one implementation
`of a remote device 32 conforming to the present invention.
`AS will be discussed below, the remote device 32 is in
`communication with one or more instruments 36 employed
`at a remote monitoring location 34. The remote device 32
`optimizes the use of wireleSS data communication technolo
`gies to transmit and receive instrument data over a network
`40 between the remote monitoring locations 34 and the
`central computer 30. As used herein, the phrase “wireless
`data communication technologies” is meant to refer to any
`data communication technology that may be employed to
`transmit data wirelessly, such as CDPD, GPRS, CDMA
`1XRTT, EDGE, WCDMA, CDMA 3XRTT, and the like.
`The remote device 32 routes and manages data transmission
`between the instruments and the central computer 30. The
`remote device 32 of FIG. 3 is particularly adapted for
`CDPD-type wireless data transmission. However, the device
`may be configured Similarly to Support any wireleSS data
`communication technology. The remote device 32 may be
`configured to monitor instruments and then communicate
`with the central computer upon receipt of a request from the
`central computer 30. The remote device 32 may also be
`configured to monitor instruments and communicate with
`the central computer 30 without a request or poll from the
`central computer.
`0033. The remote device 32 includes an external connec
`tor (not shown) to attach to a power transformer and is
`configured to operate with an input voltage from 8 to 30
`Volts. Alternatively, especially when employed at monitor
`ing locations that do not have a ready electrical power
`Supply, the remote device can be powered by a remote power
`Source, Such as one or more batteries, a Solar array, or the
`
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`
`like. To provide a Visual indication that the remote device is
`powered, the remote device includes a light emitting diode
`(“LED") mounted externally on the housing that blinks
`when the remote device has power and is operating. In one
`example, the remote device is housed in a environmentally
`protected housing having a dimension of about 5.31"LX
`3.35"WX1.5"H.
`0034. The remote device 32 includes a central processing
`unit (“CPU”) 48, such as a Rabbit 2000TM processor. The
`CPU 48 is connected with or includes one or more memory
`units 50, Such as a random acceSS memory, read only
`memory, CD-ROM, or the like. In addition, the CPU 48
`includes a brownout detector and a low Voltage detector. In
`a remote device that communicates with the central com
`puter using CDPD, a CDPD modem 52 is connected with the
`CPU 48. A first universal asynchronous receiver-transmitter
`(“UART) 54 is connected between the CPU 48 and the
`CDPD modem 52 to manage asynchronous serial commu
`nication therebetween. In a remote device that communi
`cates with the central computer using GPRS, a GPRS
`modem is connected with the CPU. In a remote device
`employing other wireleSS data communication technologies,
`the appropriate modem or communication processor is oper
`ably connected with the CPU. In one particular configura
`tion, an external TNC type female connector (not shown) is
`connected to the CDPD modem. The TNC connector pro
`vides a connection point for an antena 56.
`0035) The remote device also includes a RS232 serial
`communications link 58 and a RS485 serial communication
`link 60 for interfacing with PLCs and other instruments. A
`RS232 three-wire transceiver 62 is connected with the CPU
`48 to transmit and receive signals on the RS232 serial link
`58. In one example, a second UART 64 manages asynchro
`nous communications between the RS232 transceiver 62 and
`the CPU 48. An external RS232 DB9 connector (not shown)
`is attached to the housing and connected with the RS232
`transceiver 62 to provide a connection point for an RS232
`Serial cable.
`0036) The remote device 32 further includes a RS485
`two-wire transceiver 66 connected with the CPU 48 via a
`third UART 68 to manage asynchronous communications
`over the RS485 serial communication link 60. In one
`example, the RS485 transceiver 66 is configured as a two
`wire interface with optional ground, and as a non-terminated
`master. The remote device 32 has user accessible external
`terminals to attach the physical RS485 wires and ground.
`0037. In addition to serial link channels, one particular
`embodiment of the remote device 32 may further include
`one or more analog and/or digital input, output or input/
`output (“I/O”) ports (70, 72). The I/O ports allow the remote
`device to interface with traditional SCADA instrumentation.
`In one particular example, the remote device 32 includes
`four analog input ports, four digital output ports, and eight
`digital input ports. The analog input ports are connected to
`a 12 bit analog-to-digital (A/D) converter 74. The A/D
`converter 74, the analog output ports, and the digital ports
`are each connected with the CPU 48. The four analog inputs
`are differential four-to-twenty milliamp analog inputs. Each
`analog input port is accurate to 0.1% of full Scale, has an
`internal 250 ohm terminating resistor, and is calibrated and
`Scaled using local menus.
`0.038. The remote device 32 may include a menu program
`Stored in memory for local Set-up and configuration of the
`
`remote device. The menus provide a convenient way to Set
`up, enable and configure various aspects of the remote
`device associated with Serial link communication to instru
`ments and the central computer, analog and digital port
`configurations, wireless communication parameters, and
`other features of the remote device. To configure the remote
`device, a user connects a RS232 serial cable to the DB9
`connector. Once physically connected, the user can use any
`terminal program, Such as HyperTerminal", that is config
`ured to 38400N81 to access the menus. Once the remote
`device is configured by way of the menus, the remote device
`configuration is Stored in non-volatile memory.
`0039. In one particular implementation, the remote
`device 32 is configured to support ModiconTM MODBUS/
`RTU and MODBUS/ASCII protocols, which allow the
`remote device to interface directly over one of the Serial
`links to PLCs and other instruments used to monitor and
`control equipment at a remote location. Besides the Modi
`con" protocols, the remote device also Supports “pass
`through' communication mode which allows raw data to be
`passed between a Socket on the central computer 30 and an
`instrument via one of the Serial links of the remote device.
`The pass through communication mode converts the remote
`device into a virtual Serial link, allowing data and commands
`to pass directly between the central computer and one of the
`instruments connected with the remote device. It should be
`recognized that the particular implementations of a remote
`device to support the ModiconTM protocols and pass through
`communications are representative embodiments or
`examples of the present invention, and that other protocols
`and methodologies may be implemented in a remote device
`conforming to the present invention.
`0040. A summary of the state of each analog and digital
`I/O port (70, 72) is available by locally accessing the menus
`or remotely accessing the menus from the central computer.
`For example, whether a digital input port or output port is
`“on” or “off, and the Voltage at an analog input or output
`may be determined through the menu structure. Each digital
`output is user configured for Sinking or Sourcing, and is
`limited to 30 volts maximum and 500 milliamps maximum.
`The control and State of each digital output is available using
`the local menus and/or remotely using the central computer.
`The digital inputs may be optically isolated and may have an
`input threshold of 5 volts or greater. The state of each digital
`input is available using the local menus and/or remotely
`using the central computer.
`0041. The remote device 32 is configured in a master/
`Slave arrangement Such that the remote device routes mes
`Sages between internal transceivers. Configured as Such, a
`remote device may receive commands directly from the
`central computer 30 or may receive and route commands to
`an instrument connected with the remote device. Thus, the
`remote device is configured to discriminate between mes
`Sages intended for it and messages intended for an instru
`ment. Using the menus, the user Sets the Slave and master
`transceivers, baud rate, and remote protocol. The remote
`protocol or transmission mode (e.g., Modbus RTU or Mod
`bus ASCII) is the protocol operating on the RS485 or RS232
`interface. The remote device is typically configured as the
`master. Although in Some instances, Such as inter-remote
`device communications, one remote device may be a master
`and another remote device a slave. The remote device, in one
`example, Supports serial link bauds rates of 9600N82,
`
`IPR2023-00626 Page 00009
`
`

`

`US 2003/0174070 A1
`
`Sep. 18, 2003
`
`960OE81, 9600O81, 1920ON82, 1920OE81, 19200O81,
`38400N82,38400E81, and 38400O81. The user also sets the
`Modbus/RTU address for the remote device.
`0042. The remote devices 32 communicate with the net
`work 40 using a wireleSS data communication technology. In
`the case of the embodiment of the remote device of FIG. 3,
`various CDPD communication parameters may be config
`ured using the menus accessible via the RS232 Serial con
`nection 58. In one example, the user may configure the
`Source CDPDIP address of the remote device 32, the Source
`port, the destination IP address, the destination port, and the
`cellular provider. The source IP address of the remote device
`is used to identify the remote device 32 in an IP network.
`Packets destined for the remote device 32 (e.g., packets
`transmitted from the central computer) will include the
`Source IP address of the remote device in the header. In the
`case of CDPD, a cellular service provider will typically
`provide the unique IP address of the remote device 32. The
`Source port and the destination port correspond to the port
`upon which messages are received from the central com
`puter 30 and the port from which messages are transmitted
`from the remote device to the central computer 30, respec
`tively. The destination IP ad