WO1997019393A1 - Distributed environmental process control system - Google Patents
Distributed environmental process control system Download PDFInfo
- Publication number
- WO1997019393A1 WO1997019393A1 PCT/US1996/018043 US9618043W WO9719393A1 WO 1997019393 A1 WO1997019393 A1 WO 1997019393A1 US 9618043 W US9618043 W US 9618043W WO 9719393 A1 WO9719393 A1 WO 9719393A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- branch
- controller
- network
- node
- ofthe
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/418—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM]
- G05B19/4185—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM] characterised by the network communication
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/042—Programme control other than numerical control, i.e. in sequence controllers or logic controllers using digital processors
- G05B19/0421—Multiprocessor system
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/418—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM]
- G05B19/4185—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM] characterised by the network communication
- G05B19/4186—Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control [DNC], flexible manufacturing systems [FMS], integrated manufacturing systems [IMS], computer integrated manufacturing [CIM] characterised by the network communication by protocol, e.g. MAP, TOP
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L12/403—Bus networks with centralised control, e.g. polling
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/26—Pc applications
- G05B2219/2638—Airconditioning
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/31—From computer integrated manufacturing till monitoring
- G05B2219/31188—Combine csma-cd and tdm time multiplexed for rapid status exchange
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33144—Module clock, synchronised by controller message, to send message in time slice
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33187—Serial transmission rs232c, rs422, rs485 communication link
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33248—Time window for each controller or controlled function
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33251—Schedule periodic and aperiodic traffic, real time, time critical
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/33—Director till display
- G05B2219/33252—Real time synchronous transmission, model
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/30—Nc systems
- G05B2219/50—Machine tool, machine tool null till machine tool work handling
- G05B2219/50102—Store history of operation, after power failure, restart from history, journal
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/40—Bus networks
- H04L2012/4026—Bus for use in automation systems
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
Definitions
- This invention relates in general to process control systems. More particularly this invention relates to a microprocessor based distributed control system for indoor environmental control, such as laboratory ventilation control.
- the invention relates to systems wherein control and monitoring of the heating, cooling and ventilation control devices of a plurality of individual laboratory rooms, including the control of make up air supply requirements in response to the variable exhaust requirements of devices such as fume hood exhaust valves, may be interconnected and integrated in a system of high speed communication networks, thereby enabling the real time monitoring and control of all of the devices included in the system from any point in the system.
- the invention is more generally applicable in providing means for the highly flexible programming, control and monitoring of process systems by controlling the pumps, boilers, chillers, heaters, agitators, mixers and the like that carry out the process.
- variable volume fume hoods in a laboratory space generally requires their integration in a room ventilation control system that includes provision for the supply of make up air, the temperature conditioning of the supply air and the provision of a room exhaust device to exhaust differences between the volume of air being supplied to the laboratory space and the volume being exhausted through the fume hoods, including any user defined positive or negative offset.
- electronic controllers have been developed having the capability, based on inputs from various devices such as air flow valves, air flow sensors, thermostats and the like, to comply with user defined minimum or maximum conditions for air flow and temperature, and to balance the supply and exhaust flows by controlling either a make up air supply device or a general exhaust device or both.
- the system be networked in such a manner that the control and monitoring of ventilation devices in any of a plurality of laboratory rooms may be performed from remote locations. It is further desirable to provide a networked process control and monitoring system whereby real time transmission of rapidly variable operational data generated by a plurality of control devices located in a plurality of physically separated rooms or spaces is effected efficiently and reliably.
- Fig. 1 is a block diagram ofthe network topology of an embodiment of the present invention
- Fig. 2 is a timing diagram ofthe network communications ofthe embodiment ofthe present invention
- Fig. 3 is a schematic representation of a command table and command sent over the primary network
- Fig. 4 is a block diagram of a branch controller.
- the process control system in accordance with the present invention includes a backbone or primary network 101 of nodes 103 and a plurality of branch networks 105 each controlled by a node 103 on the primary network 101.
- the primary network 101 may form a building-wide communications system, while each branch network 105 serves a sub-system such as a room, small area or laboratory.
- the system of networks ofthe invention interconnects, on a peer-to-peer basis, primary network nodes 103 comprised of microprocessor-based branch controllers, each of which controls, in a master-slave relationship over the branch network, a plurality of device controllers 107, such as air flow valve controllers.
- the primary network 101 and the branch networks 105 are each serial multi-drop digital communication systems running at 375 Kbaud.
- the primary network is a peer-to-peer, time division multiplexed synchronous data link control (SDLC) communications platform for interconnecting up to 100 branch controllers 103.
- each branch controller 103 may be connected via its branch network 105 to as many as 31 device controllers 107.
- the branch networks 105 use both time division multiplexing and individual addressing of device controllers 107 to collect and transfer data.
- the branch network 105 operates as a master-slave communications network with the branch controller 103 as the master.
- Each branch controller 103 and device controller 107 preferably includes a serial port 109 such as a EIA-232 port which allows the user to access any point on the system, and serves as a general purpose serial input output gateway.
- a serial port 109 such as a EIA-232 port which allows the user to access any point on the system, and serves as a general purpose serial input output gateway.
- a personal computer 11 1 may be attached as a terminal device.
- the Primary network 101 interconnects a plurality of microprocessor based branch controllers 103 in a peer-to-peer relationship whereby each branch controller 103 may issue commands to and receive responses from any other branch controller 103 on the primary network 101, and through such other branch controller, to any device controller 107 in the system.
- each ofthe branch controllers 103 on the primary network 101 inco ⁇ orates a serial communications controller chip (Fig. 4, 408), such as the Zilog 85230 Enhanced Serial Communication Controller (ESCC), and communicates in a time division multiplexing (TDM) format.
- the primary network 101 illustrated is an SDLC network.
- the SDLC protocol is well-known, and used for its simplicity. However, other more complex protocols may be used in suitable applications as would be understood by those skilled in the art.
- Each branch controller 103 forming a node on the primary network 101 is assigned a unique address, for example via a set of DIP switches (Fig. 4, 41 1). This address is used to determine a communication time slot (e.g., Fig. 2, 201 and 203), in relation to a synchronization signal 205 issued on the primary network 101 by one ofthe branch controllers 103, the synchronizing station branch controller. Each branch controller 103 may only communicate on the primary network 101 in its assigned time slot 201, 203, etc.
- each synchronization period 205 includes a preset time 207 for each branch controller 103 to conduct a branch network control cycle 209 including communication with the device controllers 107 on its branch network 105, as further described below.
- each branch controller 103 on the primary network 101 reads its primary network address and calculates its time slot location (201, 203, et seq.). For each branch controller 103 the appropriate time slot is determined by multiplying a time slot multiple, equal in the illustrated embodiment to 1350 ⁇ S, by the branch controller address minus 1, and adding to this result the gap time between time slots and the time slot 209 allocated for the branch network control cycle 209 (32 mS in the example embodiment). Each branch controller 103 on the primary network 101 accordingly carries out the following calculation:
- Time from synch (time slot multiple) * (address - I) +gap time + (control cycle time slot)
- branch controller addresses after 50 would be required to add an additional 32 mS in calculating the time location of their communication slot.
- the branch controller 103 with the lowest primary network address is arbitrarily designated as the synchronizing station, and it issues a synchronization signal 205 at predefined intervals based on the system size, which determines the synchronization interval.
- the illustrated embodiment enables three system sizes, large, medium and small, and the appropriate system size is set for example by DIP switches in each branch controller 103 in the system.
- the primary network 101 of a large system is resynchronized every 100 time slots, a medium system every 64 time slots, and the small system every 32 time slots.
- the synchronization signal 205 is issued by the synchronizing station branch controller for example every 75.2, 1 18.2 or 199 mS depending on the user selection of a small, medium or large system.
- the control cycles 209 of all ofthe branch networks 105 are collectively initiated once per synchronization cycle.
- the time slots may optionally be adjusted to include an additional 32 mS interruption, for example between branch controller communication time slots 50 and 51, in order to insert a second branch network control cycle 209 in the interruption. This option serves to maintain a maximum limit of 100 mS between branch network control cycles.
- the present invention includes means, in the event the synchronizing station branch controller 103 fails to issue a synchronization signal 205, or the synchronization signal 205 fails to reach a part of the primary network 101 , for the branch controllers 103 not receiving a timely synchronization signal 205 then to execute in sequence an ascending time-out sequence, the outcome of which is to replace the synchronizing branch controller 103 with the branch controller 103 having the next lowest address in each intact segment ofthe primary network 101.
- the time-out value is calculated based on network address, as follows.
- Each branch controller 103 has a timer which resets upon receipt by the branch controller ofthe primary network synchronizing signal 205. If the timer of any branch controller 103 expires before receipt of a valid synchronization signal 205, that branch controller proceeds to issue a synchronization signal 205 and thereafter to act as the synchronizing branch controller. However, the branch controller relinquishes this task on any subsequent receipt of a synchronization signal 205 from another branch controller 103 having a lower address on the primary network 101. Each branch controller 103 also pauses on the detection of an error during its own issuance of a synchronization signal 205, to check for receipt of a synchronization signal 205 from a branch controller 103 with a lower address on the primary network 101. This collision scheme permits reconnection of a broken cable and incremented powering up of branch networks 105 during which a lower address branch controller 103 may be brought on line subsequent to other branch controllers 103 having a higher address on the primary network 101.
- branch controller Unit 1 may communicate on the primary network 101 only during a single time slot 201 per synchronization signal 205, beginning approximately 1600uS after the completion of a 32 mS time slot 207 reserved for all branch controllers 103 to conduct their respective branch network control cycle 209. Effectively simultaneously for all branch controllers 103 on the primary network 101, the branch network control cycle 209 is initiated by a synchronization signal 21 1 from the synchronizing station branch controller 103.
- each branch controller 103 has the opportunity, over a time slot 213 of approximately 5mS duration, to further interrogate each device controller 107 on its branch network 105.
- This time slot 213 is sufficient for the branch controller 103 to address one transmission to each device controller 107 on its branch network 105 and subsequently to receive one transmission back from each device controller 107.
- the branch controllers 103 are each allotted, in sequence of increasing primary network address number, a time slot 201 , 203 et seq. in which to communicate on the primary network 101 , each of these time slots being separated by 1.35 mS.
- the time slots 201, 203, et seq. assigned to each ofthe branch controllers 103 for primary network 101 communications are sufficiently wide to accommodate two transmissions by each branch controller 103, each limited to 16 bytes in the illustrated embodiment.
- Each such transmission issued on the primary network 101 by a branch controller 103 to another branch controller 103 may be directed to a different address and may be a command or a response to a command.
- Typical examples of commands a branch controller 103 might issue to another branch controller 103 include a request for flow data by a branch controller 103 serving as a central data collection station or a response to a query by another branch controller 103.
- each branch controller 103 includes a memory (Fig. 4, 401), as discussed below.
- the memory 401 holds a primary network command table (Fig. 3, 301), which contains both "persistent commands", created by I/O requests from a suitable programming tool, not shown, and "temporary commands" generated by the branch controller 103 in response to requests received by the branch controller 103 over either the primary network 101 or the branch network 105, or at a serial port 109 ofthe branch controller 103, such as an EIA-232 port.
- Each branch controller 103 maintains temporary commands in its command table 301 until it has transmitted a response to the temporary command to the source controller originating the command. If there are more than two messages awaiting execution in the branch controller command table (Fig. 3, 301), the branch controller 103 issues them sequentially, in a conventional first in first out (FIFO) manner.
- FIFO first in first out
- Each entry into the command table (Fig. 3, 301) of any branch controller 103 includes code representing message status 303, byte count 305, destination address 307, opcode (command) 309, and data 311.
- the branch controller 103 Upon the actual transmission of each entry in its command table 301, the branch controller 103 additionally appends a sequence number 313 to the transmission. This sequence number 313 accompanies the transmission to the target branch controller 103, or device controller 107, and is in turn appended to the response, as a result of which the sending branch controller 103 is able to locate, in its command table 301, the source ofthe command evoking this response.
- the response Once the response is checked at the command table 301 it may be routed to the serial port 109 ofthe branch controller 103 or to a device controller 107 as appropriate.
- each branch network 105 interconnects a branch controller 103 with up to 31 device controllers 107, such as air flow device controllers, in a master slave mode in which the device controllers 107 communicate only in response to interrogation by the branch controller 103.
- the branch networks 105 enable the branch controllers 103 to execute flow summation and balancing calculations for air flow devices under their respective supervision, and also enable various data to be collected by the branch controllers 103 from the device controllers 107 in their respective branch networks 105, during the command/response time slot 213 ofthe branch network control cycle time slot 207 ofthe primary network 101.
- Each branch controller 103 can be a relatively simple device, as shown in the block diagram of Fig. 4.
- the basic components of a branch controller 103 are a microprocessor 402 and its necessary supporting components. In the illustrated embodiment, these include an EPROM 412 holding executive software instructions, network operation software instructions and environmental control software instructions; a RAM 406 holding any free programs downloaded to the branch controller, data collected during network operations or environmental control operations; a serial communications controller 408; and a processor clock 410.
- the branch controller 103 may also have a RAM 405 for performing scratch pad calculations.
- the microprocessor 402 selected for the illustrated embodiment is an industry-standard Intel 8031 device, which includes a universal asynchronous receiver/transmitter (UART) 404, which can sustain the communication speeds required by the branch network 105.
- the preferred serial controller 408 is a Zilog 86230 Enhanced Serial Communications Controller (ESCC).
- ESCC Zilog 86230 Enhanced Serial Communications Controller
- Branch controllers 103 communicate with other devices via one of three serial ports.
- An EIA-232 port 109 is provided for communication with terminal devices, gateways and other external hardware.
- the EIA-232 standard defines a well-known serial communications medium including separate transmit 407 and receive 409 lines.
- Two EIA-485 ports 416, 418 provide communication respectively with the primary network 101 and with the branch network 105.
- the EIA-485 standard defines a well-known serial communications medium including one balanced differential line, which may be used for bi-directional communication.
- One EIA-485 port 416 is controlled by the ESCC to communicate over the primary network 101.
- the second EIA-485 port 418 is controlled by the UART 404 built into the 8031 microprocessor to communicate over the branch network 105.
- the branch controller 103 may include an I/O port 420 for receiving a customized I/O module.
- I/O module includes five analog input channels serviced through a multiplexer 422 to an individual analog-to-digital converter 424, two analog output channels (not shown) controlled by the microprocessor 402 through a connection to the microprocessor address and data bus 403, and two digital output channels 428.
- Such an I/O module may, for example, be used to connect the branch controller 103 to older devices lacking digital controls or to digital devices not specifically designed for use in the described configuration.
- the UART 404 ofthe 8031 microprocessor 402 is configured to communicate at '/ 32 ofthe processor clock 410 speed.
- the processor clock 410 of all ofthe branch controllers 103 and device controllers 107 runs at a frequency of 12MHz, producing a communication speed of 375 Kbaud.
- the branch network 105 is also based on time division multiplexing.
- the 8031 microprocessor 402 employed in the illustrated embodiment generates 1 1 -bit frames, each of which contains start, stop, and utility bits and 8 bits of data.
- the 8031 UART 404 and the UART used on device controllers 107 may be set up to only receive data if the utility bit is set in a particular transmission, thereby enabling a device controller 107 to ignore transmissions from its branch controller 103 that are intended for other device controllers 107 on the same branch network 105.
- the physical medium for all network connections in the illustrated embodiment is a shielded, twisted-pair type of communications cable.
- any convenient bi-directional medium capable of sustaining the required communications bandwidth may be used, including other types of cable, fiber optic infrared and other wireless connections.
- the branch network control cycle 209 appropriate to each branch controller 103 is initiated each time the branch controllers 103 receive a synchronization signal 205 over the primary network 101 (except for the synchronizing station branch controller 103, which initiates its branch network control cycle 209 upon issuing its synchronizing signal 205).
- the branch controller 103 initiates its branch control cycle 209 by issuing a branch network synchronization command 21 1 to the device controllers 107 on its branch network 105. (In "large" systems, this command may optionally be issued again, for example between the primary network 101 address 50 and 51 time slots.)
- this command may optionally be issued again, for example between the primary network 101 address 50 and 51 time slots.
- the branch controllers 103 during the course ofthe primary network communications period 208 are each assigned a unique time slot (e.g.
- each device controller 107 on a branch network 105 is assigned a unique time slot 212 within the branch network control cycle 209, determined by the address ofthe device controller 107 in the branch network 105, in which to communicate in response to the branch synchronization command 21 1.
- Communications with external devices over EIA-232 ports 109 ofthe branch controllers 103 may take place during each gap 219 between time slots, except that no communications are permitted during time slot 217.
- each device controller 107 reads its address and calculates its time slot location.
- the time slot 212 of each branch network device controller 107 is determined by multiplying its address minus 1 by a time slot multiple, and adding a gap time, as in the following calculation:
- Time from synch (time slot multiple) x (address - J)) + gap time
- each device controller time slot 212 has a duration of 600 ⁇ S.
- each device controller 107 may in their respective communications time slots 212 on the branch network 105 only transmit responses to a set of application-specific commands defined by the user ofthe system.
- the response of each device controller 107 to the branch synchronization command 21 1 thus includes three items of data in the illustrated embodiment.
- these three items of data are signals respectively representative of (a) exhaust setting, (b) supply setting, and ⁇ a user selected third parameter.
- each branch controller 103 uses the collected information to make any prescribed calculation and to issue commands 215 based thereon on the branch network 105.
- each branch controller 103 calculates during time slot 217 the aggregate supply and exhaust for the laboratory room that it supervises, and a difference from prescribed conditions (including any user defined offsets or any user defined minimum or maximum flow or temperature limits). The branch controller 103 then calculates also during time slot 217 and issues 215 the setpoints necessary to properly balance the system in compliance with all user defined conditions and limits.
- control of the make up air cycle follows the time division multiplex sequence described above generally for the branch network control cycle 209, which allows for position/address independent connection to the branch controller 103 ofthe device controllers 107 respectively controlling the supply, exhaust and other controlled devices supervised by the branch controller 103 on its branch network 105.
- each device controller 107 or other branch network device responds in sequence, in its allocated time slot 212, by providing the branch controller 103 with supply, exhaust, status and flow feedback data. Upon receipt from each device controller 107 this information is immediately applied by the branch controller 103 to the calculation of the make up air equation, through the maintenance of a running tally summing the exhaust and supply information as it is received sequentially from the device controllers 107 on the branch network 105.
- the branch controller 103 completes its calculation of the make up air equation, and then it issues on the branch network 105 a single command transmission, the make up air cycle response, that includes respectively the make up air flow set point, general exhaust flow set point, the total exhaust, supply air flow and other pertinent data.
- the branch controller 103 On receipt of this transmission from the branch controller 103, those device controllers 107 on its branch network 105 that are configured respectively as the make up air device controller, the general exhaust valve controller, or a bypass valve controller, recognize which portion or portions ofthe transmitted command data, if any, are pertinent to its operation, and proceed to execute any pertinent commands.
- Branch Network Command/Response Activity recognize which portion or portions ofthe transmitted command data, if any, are pertinent to its operation, and proceed to execute any pertinent commands.
- a set time slot 213 is allotted for the branch controller 103 to generate commands to individual device controllers 107 on its branch network 105 and to obtain a responsive transmission from each device controller 107, as addressed sequentially.
- command/response mode may importantly be employed to deliver configuration commands to the device controllers 107. Commands may also be issued by the branch controller 103 in response to error conditions or alarms detected during the branch network control cycle 209, or requests made for point data (calculated or actual) contained at the device controller 107. This time slot 213 is also suitable for the issuance by the branch controller 103 of commands to initiate special sequences, such as, in laboratory ventilation applications, a purge-vent sequence.
- each branch controller 103 and each device controller 107 contains a serial port 109, such as an EIA-232 compliant port.
- the serial ports 109 ofthe branch controllers 103 allow the user to access via appropriate software from any branch controller 103 every other branch controller 103 and every device controller 107 on the system, and enable a highly flexible, balletic interaction among all of the controllers on the primary network 101 and the branch networks 105.
- a command issued at any serial port 109 is gathered and verified by that port's host branch controller 103 or device controller 107. Once the command ' s destination is determined, it is either issued locally over the branch network 105, or assigned a sequence number and placed in the primary network or branch network command tables (Fig. 3, 301) of the local branch controller 103.
- the command travels through the branch network controller 103 to the desired destination, where it is acted upon, and, in due time, responded to.
- the response contains the sequence number and the opcode assigned to the command at origination.
- the branch controller 103 uses the sequence number and the opcode to route the message back to the serial port 109 that originated the command.
- a command entered through a serial port 109 and destined for a device or device controller 107 on a remote branch network 105 is routed in substantially the same way.
- the branch controller 103 ofthe branch network 105 receiving the command (the local branch controller) it is gathered and verified as a valid command, its destination is determined, and the command is placed in the appropriate command table (Fig. 3, 301) of the local branch controller.
- a command directed to a device controller 107 on a remote branch network 105 and connected to a different branch controller 103, requesting user status is assigned a sequence number and the appropriate opcode by the local branch controller 103, and it is placed in the primary network "temporary command" table ofthe local branch controller.
- the command is thereafter transmitted to the remote target branch controller 103 during the primary network time slot 201, 203, etc. ofthe local branch controller 103.
- the remote branch controller 103 gathers the command, verifies it, and places it (along with the command's sequence number and opcode) in its branch network command table (Fig. 3, 301).
- the request is issued by the remote branch controller 103 to the target device controller 107.
- the target device controller 107 responds with the requested data, maintaining the sequence number and opcode.
- the remote branch controller 103 takes the response from its device controller 107 and places it in its command table (Fig. 3, 301).
- the response is passed back to the local branch controller 103.
- the local branch controller 103 receives this response and, based on the sequence number and opcode, marks the original command in its command table (Fig. 3, 301) as received. Additionally, this opcode is used to determine the final destination ofthe response. In this case it is sent to the serial port command table. The message is then transmitted out the serial port 109 at the next available opportunity.
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP9519771A JPH10511795A (en) | 1995-11-17 | 1996-11-13 | Distributed environment process control system |
DE19681655T DE19681655T1 (en) | 1995-11-17 | 1996-11-13 | Distributed process control system for environmental conditions |
AU77261/96A AU7726196A (en) | 1995-11-17 | 1996-11-13 | Distributed environmental process control system |
SE9801697A SE521298C2 (en) | 1995-11-17 | 1998-05-14 | Method of communication in a computer network and such computer network to control device controllers in real time |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/559,822 | 1995-11-17 | ||
US08/559,822 US5831848A (en) | 1995-11-17 | 1995-11-17 | Distributed environmental process control system |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997019393A1 true WO1997019393A1 (en) | 1997-05-29 |
Family
ID=24235172
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1996/018043 WO1997019393A1 (en) | 1995-11-17 | 1996-11-13 | Distributed environmental process control system |
Country Status (6)
Country | Link |
---|---|
US (1) | US5831848A (en) |
JP (1) | JPH10511795A (en) |
AU (1) | AU7726196A (en) |
DE (1) | DE19681655T1 (en) |
SE (1) | SE521298C2 (en) |
WO (1) | WO1997019393A1 (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998046978A1 (en) * | 1997-04-15 | 1998-10-22 | Phoenix Controls Corporation | Networked air measurement system |
US6199136B1 (en) * | 1998-09-02 | 2001-03-06 | U.S. Philips Corporation | Method and apparatus for a low data-rate network to be represented on and controllable by high data-rate home audio/video interoperability (HAVi) network |
NL1017054C2 (en) * | 2000-01-10 | 2001-07-18 | Giersiepen Gira Gmbh | Electrical installation system. |
WO2006022569A1 (en) | 2004-08-17 | 2006-03-02 | Obshchestvo S Ogranichennoy Otvetstvennostiuy 'promishlennaya Gruppa ' Finprom - Resurs' | Device for controlling a system of objects through a power line and an adapter therefor |
CN106325233A (en) * | 2015-07-07 | 2017-01-11 | 刘华 | Visual programming logic distribution control system and implementation method |
Families Citing this family (49)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH10340199A (en) * | 1997-06-09 | 1998-12-22 | Nec Shizuoka Ltd | Computer system |
SE520936C2 (en) * | 1998-04-24 | 2003-09-16 | Axis Ab | Collecting data over network from peripheral devices in order to control them via internet, using data packets sent over separate couplings between network operated device, activated nodes and target nodes |
US6421743B1 (en) * | 1999-09-23 | 2002-07-16 | Coactive Networks, Inc. | Method and system for data transformation in a computer network |
US20030055900A1 (en) * | 2000-02-02 | 2003-03-20 | Siemens Aktiengesellschaft | Network and associated network subscriber having message route management between a microprocessor interface and ports of the network subscriber |
FR2811067B1 (en) | 2000-07-03 | 2002-09-27 | Alain Katz | FRONTAL AIR SPEED CONTROL SYSTEM AND METHOD FOR AIR EXTRACTION EQUIPMENT, IN PARTICULAR LABORATORY HOODS, AND DEVICE IMPLEMENTED |
US7020156B2 (en) * | 2000-12-15 | 2006-03-28 | American Standard International Inc. | Multiple device communications |
US20020082884A1 (en) * | 2000-12-22 | 2002-06-27 | Moroney Brady J. | Manufacturing and testing communications system |
US6782351B2 (en) | 2001-09-11 | 2004-08-24 | Purechoice, Inc. | Air quality monitoring and space management system coupled to a private communications network |
ATE530961T1 (en) * | 2002-01-28 | 2011-11-15 | Siemens Industry Inc | BUILDING SYSTEM WITH REDUCED WIRING REQUIREMENTS AND EQUIPMENT |
US7349761B1 (en) * | 2002-02-07 | 2008-03-25 | Cruse Mike B | System and method for distributed facility management and operational control |
US6783367B1 (en) * | 2002-02-19 | 2004-08-31 | Cisco Technology, Inc. | Method and system for providing a global product services electronic laboratory |
DK1481203T4 (en) * | 2002-03-01 | 2016-11-21 | Windowmaster As | Method and control system for controlled operation of moving parts |
CN100466522C (en) * | 2005-12-13 | 2009-03-04 | 华为技术有限公司 | Farend access communication system, and control method |
US10271293B2 (en) | 2011-11-18 | 2019-04-23 | Apple Inc. | Group formation within a synchronized hierarchy of peer-to-peer devices |
US9516615B2 (en) | 2011-11-18 | 2016-12-06 | Apple Inc. | Selection of synchronization stations in a peer-to-peer network environment |
US9124446B2 (en) * | 2012-09-28 | 2015-09-01 | Bristol, Inc. | Methods and apparatus to implement a remote terminal unit network |
JP6263836B2 (en) * | 2013-01-15 | 2018-01-24 | オムロン株式会社 | Control apparatus and control method |
US9109981B2 (en) | 2013-03-15 | 2015-08-18 | Aircuity, Inc. | Methods and apparatus for indoor air contaminant monitoring |
CN106170780B (en) * | 2014-01-10 | 2019-10-18 | 飞利浦灯具控股公司 | More host bus |
CN103984659B (en) * | 2014-05-15 | 2017-07-21 | 华为技术有限公司 | The method and apparatus that timesharing uses serial ports |
US10374904B2 (en) | 2015-05-15 | 2019-08-06 | Cisco Technology, Inc. | Diagnostic network visualization |
US9967158B2 (en) | 2015-06-05 | 2018-05-08 | Cisco Technology, Inc. | Interactive hierarchical network chord diagram for application dependency mapping |
US10536357B2 (en) | 2015-06-05 | 2020-01-14 | Cisco Technology, Inc. | Late data detection in data center |
US10142353B2 (en) | 2015-06-05 | 2018-11-27 | Cisco Technology, Inc. | System for monitoring and managing datacenters |
JP6165286B1 (en) * | 2016-02-29 | 2017-07-19 | 株式会社安川電機 | Motor control system, robot system, and motor control system communication method |
US10289438B2 (en) | 2016-06-16 | 2019-05-14 | Cisco Technology, Inc. | Techniques for coordination of application components deployed on distributed virtual machines |
US10708183B2 (en) | 2016-07-21 | 2020-07-07 | Cisco Technology, Inc. | System and method of providing segment routing as a service |
US10490058B2 (en) * | 2016-09-19 | 2019-11-26 | Siemens Industry, Inc. | Internet-of-things-based safety system |
US10972388B2 (en) | 2016-11-22 | 2021-04-06 | Cisco Technology, Inc. | Federated microburst detection |
US10708152B2 (en) | 2017-03-23 | 2020-07-07 | Cisco Technology, Inc. | Predicting application and network performance |
US10523512B2 (en) | 2017-03-24 | 2019-12-31 | Cisco Technology, Inc. | Network agent for generating platform specific network policies |
US10594560B2 (en) | 2017-03-27 | 2020-03-17 | Cisco Technology, Inc. | Intent driven network policy platform |
US10764141B2 (en) | 2017-03-27 | 2020-09-01 | Cisco Technology, Inc. | Network agent for reporting to a network policy system |
US10250446B2 (en) | 2017-03-27 | 2019-04-02 | Cisco Technology, Inc. | Distributed policy store |
US10873794B2 (en) | 2017-03-28 | 2020-12-22 | Cisco Technology, Inc. | Flowlet resolution for application performance monitoring and management |
US10680887B2 (en) | 2017-07-21 | 2020-06-09 | Cisco Technology, Inc. | Remote device status audit and recovery |
US10554501B2 (en) | 2017-10-23 | 2020-02-04 | Cisco Technology, Inc. | Network migration assistant |
US10523541B2 (en) | 2017-10-25 | 2019-12-31 | Cisco Technology, Inc. | Federated network and application data analytics platform |
US10594542B2 (en) | 2017-10-27 | 2020-03-17 | Cisco Technology, Inc. | System and method for network root cause analysis |
CA3026918C (en) | 2017-12-14 | 2023-08-01 | Veris Industries, Llc | Energy metering for a building |
US11233821B2 (en) | 2018-01-04 | 2022-01-25 | Cisco Technology, Inc. | Network intrusion counter-intelligence |
US10574575B2 (en) | 2018-01-25 | 2020-02-25 | Cisco Technology, Inc. | Network flow stitching using middle box flow stitching |
US10798015B2 (en) | 2018-01-25 | 2020-10-06 | Cisco Technology, Inc. | Discovery of middleboxes using traffic flow stitching |
US10999149B2 (en) | 2018-01-25 | 2021-05-04 | Cisco Technology, Inc. | Automatic configuration discovery based on traffic flow data |
US10826803B2 (en) | 2018-01-25 | 2020-11-03 | Cisco Technology, Inc. | Mechanism for facilitating efficient policy updates |
US11128700B2 (en) | 2018-01-26 | 2021-09-21 | Cisco Technology, Inc. | Load balancing configuration based on traffic flow telemetry |
JP6918849B2 (en) * | 2019-01-22 | 2021-08-11 | ファナック株式会社 | system |
EP3734396B1 (en) * | 2019-04-29 | 2021-09-08 | Grundfos Holding A/S | Control system and method for controlling a fluid distribution system |
CN112799359A (en) * | 2020-12-30 | 2021-05-14 | 浙江德源智能科技股份有限公司 | Flexible production line material distribution decision method and device based on MES system |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0196677A2 (en) * | 1985-04-05 | 1986-10-08 | Tsudakoma Corporation | Centralized loom control system |
US4780814A (en) * | 1987-02-09 | 1988-10-25 | Intel Corporation | Global serial channel for microcontroller |
EP0562333A2 (en) * | 1992-03-06 | 1993-09-29 | Pitney Bowes Inc. | Scheduled communication network |
EP0622712A2 (en) * | 1993-04-28 | 1994-11-02 | Allen-Bradley Company | Communication network with time coordinated station activity |
GB2283836A (en) * | 1993-11-15 | 1995-05-17 | Pitney Bowes Inc | System architecture for control applications |
GB2283887A (en) * | 1993-11-15 | 1995-05-17 | Pitney Bowes Inc | Communication system for control applications |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4742475A (en) * | 1984-06-19 | 1988-05-03 | Ibg International, Inc. | Environmental control system |
US4528898A (en) * | 1984-03-05 | 1985-07-16 | Imec Corporation | Fume hood controller |
GB8510808D0 (en) * | 1985-04-29 | 1985-06-05 | Automation & Computer Systems | Communication system |
US5086505A (en) * | 1989-06-30 | 1992-02-04 | Motorola, Inc. | Selective individual reset apparatus and method |
US5439414A (en) * | 1993-07-26 | 1995-08-08 | Landis & Gyr Powers, Inc. | Networked fume hood monitoring system |
US5562537A (en) * | 1995-05-11 | 1996-10-08 | Landis & Gyr Powers, Inc. | Networked fume hood monitoring system |
-
1995
- 1995-11-17 US US08/559,822 patent/US5831848A/en not_active Expired - Lifetime
-
1996
- 1996-11-13 WO PCT/US1996/018043 patent/WO1997019393A1/en active Application Filing
- 1996-11-13 JP JP9519771A patent/JPH10511795A/en active Pending
- 1996-11-13 AU AU77261/96A patent/AU7726196A/en not_active Abandoned
- 1996-11-13 DE DE19681655T patent/DE19681655T1/en not_active Ceased
-
1998
- 1998-05-14 SE SE9801697A patent/SE521298C2/en not_active IP Right Cessation
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0196677A2 (en) * | 1985-04-05 | 1986-10-08 | Tsudakoma Corporation | Centralized loom control system |
US4780814A (en) * | 1987-02-09 | 1988-10-25 | Intel Corporation | Global serial channel for microcontroller |
EP0562333A2 (en) * | 1992-03-06 | 1993-09-29 | Pitney Bowes Inc. | Scheduled communication network |
EP0622712A2 (en) * | 1993-04-28 | 1994-11-02 | Allen-Bradley Company | Communication network with time coordinated station activity |
GB2283836A (en) * | 1993-11-15 | 1995-05-17 | Pitney Bowes Inc | System architecture for control applications |
GB2283887A (en) * | 1993-11-15 | 1995-05-17 | Pitney Bowes Inc | Communication system for control applications |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1998046978A1 (en) * | 1997-04-15 | 1998-10-22 | Phoenix Controls Corporation | Networked air measurement system |
US6199136B1 (en) * | 1998-09-02 | 2001-03-06 | U.S. Philips Corporation | Method and apparatus for a low data-rate network to be represented on and controllable by high data-rate home audio/video interoperability (HAVi) network |
NL1017054C2 (en) * | 2000-01-10 | 2001-07-18 | Giersiepen Gira Gmbh | Electrical installation system. |
WO2006022569A1 (en) | 2004-08-17 | 2006-03-02 | Obshchestvo S Ogranichennoy Otvetstvennostiuy 'promishlennaya Gruppa ' Finprom - Resurs' | Device for controlling a system of objects through a power line and an adapter therefor |
DE202004021786U1 (en) | 2004-08-17 | 2011-02-17 | Ooo Obshschestvo S Ogranichennoy Otveetstvennostiuy "Promishlennaya Gruppa Finprom-Resurs" | Device for controlling a system of objects via a power line and adapter of this device |
CN106325233A (en) * | 2015-07-07 | 2017-01-11 | 刘华 | Visual programming logic distribution control system and implementation method |
Also Published As
Publication number | Publication date |
---|---|
SE9801697D0 (en) | 1998-05-14 |
DE19681655T1 (en) | 1998-12-10 |
SE9801697L (en) | 1998-07-17 |
JPH10511795A (en) | 1998-11-10 |
AU7726196A (en) | 1997-06-11 |
SE521298C2 (en) | 2003-10-21 |
US5831848A (en) | 1998-11-03 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5831848A (en) | Distributed environmental process control system | |
US4939753A (en) | Time synchronization of control networks | |
US5737318A (en) | Method for initializing a wireless, packet-hopping network | |
US4638313A (en) | Addressing for a multipoint communication system for patient monitoring | |
JP2005278192A (en) | Data transmission method | |
EP2453613A1 (en) | Method and apparatus for allocating and prioritizing data transmission | |
EP0125809A2 (en) | Distributed computer control system | |
JP2523882B2 (en) | Data transmission equipment | |
US6471011B1 (en) | Elevator communication controller and communication control method | |
CN111397175A (en) | Control equipment with multiple control modes, control method and air conditioning unit | |
CN100481801C (en) | Multi-user real-time communication method in ethernet communication system and ethernet communication system | |
EP1195345B1 (en) | Communication control unit for elevator system | |
EP3471353B1 (en) | Method and apparatus for communication in a motor drive application | |
JP2002158680A (en) | Searching algorithm for foundation field bus protocol | |
CN1555622B (en) | Method and device for producing program interruptions in subscribers to a bus system, and corresponding bus system | |
CA2463743A1 (en) | Method for operating an end-user of an isochronous cyclical communication system | |
JPH0828737B2 (en) | Communication system and relay device used in the system | |
EP1942070A2 (en) | Communications control system for elevators using synchronized communication in a master-slave network | |
JP2000049886A (en) | Message division communication method and communication system | |
KR100224321B1 (en) | Apparatus and control method for connection between earth station system and network management system | |
CN101645195B (en) | Recognizing telegram boundaries | |
JPS63113603A (en) | Connection system for plural programmable controllers | |
JPS6247238A (en) | Control method for occupation right of data way | |
JPH03263998A (en) | Interrupt control system for remote control system | |
JP2001285506A (en) | Autonomous distributed controller |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG UZ VN AM AZ BY KG KZ MD RU TJ TM |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 98016975 Country of ref document: SE |
|
WWP | Wipo information: published in national office |
Ref document number: 98016975 Country of ref document: SE |
|
RET | De translation (de og part 6b) |
Ref document number: 19681655 Country of ref document: DE Date of ref document: 19981210 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 19681655 Country of ref document: DE |
|
122 | Ep: pct application non-entry in european phase | ||
NENP | Non-entry into the national phase |
Ref country code: CA |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8607 |