Supervisory control system having alternate scanning

Claim 2

In a central control station for a supervisory control system having a plurality of remote stations coupled with the central control station and a group of field points associated with each remote station, the combination comprising alarm scanning signal generating means providing a plurality of alarm scanning signals for interrogating the plurality of remote stations for off-normal conditions existing thereat; control signal generating means providing a plurality of control signals for operating field points at the remote stations; transmitting means connected with said alarm signal generating means and said control signal generating means for receiving said alarm scanning signals and said control signals and communicating said alarm scanning signals and said control signals to the remote stations; and sequencing means connected with said alarm signal generating means and said control signal generating means to alternate the generating of each of said alarm scanning signals and each of said control signals whereby said transmitting means communicates said alarm scanning signals and said control signals to the remote stations in sequential alternation to permit continuous, noninterfering alarm scanning and control operations.

Claim 3

The invention as recited in claim 1 whereIn said alarm-scanning signals and said control signals include address data corresponding to the address of a remote station and signal-type data whereby selective ones of the remote stations are addressed and the signal addressing the remote stations is identified as one of said alarm scanning signals or said control signals.

Claim 4

The invention as recited in claim 1 wherein said alarm-scanning signal generating means normally generates first alarm-scanning signals having addresses corresponding to the remote stations to sequentially interrogate the remote stations for off-normal conditions, and said alarm-scanning signal generating means includes means detecting the existence of off-normal conditions at the remote stations and means generating second alarm-scanning signals having addresses corresponding to individual field points at the remote stations in response to the detection of an off-normal condition at one of the remote stations by said detecting means to sequentially scan the group of field points associated with the remote station.

Claim 5

The invention as recited in claim 3 wherein said control signal generating means generates first control signals having addresses corresponding to the remote stations and second control signals having addresses corresponding to individual field points at the remote stations whereby to address a specific field point one of said first control signals addresses the remote station with which the specific field point is associated and the succeeding second control signal addresses the specific field point.

Claim 6

The invention as recited in claim 3 wherein said alarm-scanning signal generating means includes a first counter for sequentially supplying remote station addresses for said first alarm-scanning signals, and a second counter for sequentially supplying individual field point addresses for said second alarm scanning signals.

Claim 7

The invention as recited in claim 1 wherein said control signal generating means generates first control signals having addresses corresponding to the remote stations and second control signals having addresses corresponding to individual field points at the remote stations whereby to address a specific field point one of said first control signals addresses the remote station with which the specific field point is associated and the succeeding second control signal addresses the specific field point.

Claim 8

A supervisory control system comprising a plurality of remote stations, each of said remote stations having an associated group of field points in communication therewith; each of said remote stations including a. alarm means providing an alarm signal when any of the field points in said associated group senses an off-normal condition, b. signal-type decoding means connected with said alarm means, c. function decoding means connected with said signal-type decoding means, and d. address decoding means connected with said alarm means and said function decoding means and operable in response to signals containing the address of said remote station; a central control station including a. first signal generating means providing alarm scanning signals including signal-type data and address data, b. second signal generating means providing control signals including signal-type data, data corresponding to functions to be performed at said field points and address data, and c. sequencing means connected with said first signal generating means and said second signal generating means to alternate the operation thereof to transmit said alarm scanning signals and said control signals in sequential alternation; and communication means supplying said alarm-scanning signals and said control signals to said plurality of remote stations and supplying said alarm signals from said alarm means at said remote station to said central control station, said signal-type decoding means and said address decoding means at each of said remote stations being operable upOn the transmission of one of said alarm-scanning signals containing the address of said remote station to operate said alarm means and provide an alarm signal to said central control station if an off-normal condition is sensed at any of the field points in said group associated with said remote station, said signal-type decoding means and said address decoding means at each of said remote stations being operable upon the transmission of one of said control signals containing the address of said remote station to operate said function decoding means to decode said function data and perform functions at the field points in said group associated with said remote station.

Claim 9

A supervisory control system comprising a plurality of remote stations, each of said remote stations having an associated group of field points in communication therewith; each of said remote stations including a. alarm means providing an alarm signal when any of the field points in said associated group senses an off-normal condition, b. signal-type decoding means connected with said alarm means, c. function decoding means connected with said signal-type decoding means, and d. address decoding means connected with said alarm means and said function decoding means and operable in response to signals containing the address of said remote station; a central control station including a. first signal generating means providing alarm scanning signals including signal-type data and address data, b. second signal generating means providing control signals including signal-type data, data corresponding to functions to be performed at said field points and address data, and c. sequencing means connected with said first signal generating means and said second signal generating means to alternate the operation thereof to transmit said alarm scanning signals and said control signals in sequential alternation; and communication means supplying said alarm-scanning signals and said control signals to said plurality of remote stations and supplying said alarm signals from said alarm means at said remote station to said central control station, said signal-type decoding means and said address decoding means at each of said remote stations being operable upOn the transmission of one of said alarm-scanning signals containing the address of said remote station to operate said alarm means and provide an alarm signal to said central control station if an off-normal condition is sensed at any of the field points in said group associated with said remote station, said signal-type decoding means and said address decoding means at each of said remote stations being operable upon the transmission of one of said control signals containing the address of said remote station to operate said function decoding means to decode said function data and perform functions at the field points in said group associated with said remote station.

Claim 10

The invention as recited in claim 7 wherein each of said remote stations includes analog transmitting means connected with said group of field points associated with said remote station to provide analog signals corresponding to conditions sensed at said group of field points in accordance with function data of said control signals, said communication means supplies said analog signals to said central control station, and said central control station includes receiving means for receiving and indicating the value of said analog signals.

Claim 11

The invention as recited in claim 8 wherein said field points include contacts having open and closed positions, each of said remote stations includes second transmitting means connected with said group of field points associated with said remote station to provide status signals corresponding to the position of said contacts in accordance with function data of said control signals, said communication means supplies said status signals to said central control station, and said central control station includes second receiving means for receiving said status signals.

Claim 12

The invention as recited in claim 7 wherein said first signal generating means provides first alarm-scanning signals having addresses corresponding to said remote stations and second alarm-scanning signals having addresses corresponding to individual field points, and said signal-type decoding means includes first means for detecting said first alarm-scanning signals and second means for detecting said second alarm-scanning signals, said alarm means including storage means responsive to said first detecting means and said address decoding means and gating means connected with and responsive to said storage means and said second detecting means to permit access to the individual field points addressed in said second alarm scanning signals.

Claim 13

The invention as recited in claim 7 wherein said first signal-generating means receives said alarm signals from said remote stations, and said first signal generating means includes a first circuit normally providing said first alarm-scanning signals, a second circuit providing said second alarm-scanning signals, selecting means interconnecting said first and second circuits to permit only one of said first and second circuits to be operative at one time, and alarm-detecting means responsive to said alarm signal to operate said selecting means to inhibit the operation of said first circuit and operate said second circuit whereby said remote stations are continuously scanned for off-normal conditions by said first alarm-scanning signals and when one of said remote stations providing an alarm signal is addressed, the individual field points of said group associated with said one remote station are scanned by said second alarm scanning signals.

Claim 14

The invention as recited in claim 11 wherein said alarm means receives field alarm signals from said individual field points addressed by said second alarm signals to provide a second alarm signal, said communication means applies said second alarm signal to said central control station, and said second circuit includes acknowledge means receiving said second alarm signal and providing acknowledge data to be included in the next succeeding second alarm scanning signal provided by said second circuit, said Alarm means including acknowledge decoding means responsive to said acknowledge data to remove said second alarm signal.

Claim 15

The invention of claim 12 wherein said first circuit includes a first counter responsive to said sequencing means to provide address data corresponding to successive remote stations in successive first alarm scanning signals, and said second circuit includes a second counter responsive to said sequencing means to provide address data corresponding to successive field points at said remote station in successive second alarm scanning signals, said second counter providing a change signal to said selecting means to render said first circuit operative when said second counter returns to zero.

Claim 16

The invention as recited in claim 13 wherein said second signal generating means includes a third circuit providing first control signals having addresses corresponding to said remote stations, a fourth circuit providing second control signals having addresses corresponding to individual field points, and second selecting means connected with said third and fourth circuits for alternately operating said third and fourth circuits.

Claim 17

The invention as recited in claim 14 wherein said signal-type decoding means includes third means detecting said first control signals and fourth means detecting said second control signals, each of said remote stations includes second storage means responsive to said third detecting means and said address decoding means and second gating means responsive to said second storage means and said fourth detecting means to permit access to the individual field points addressed in said second alarm signals.

Claim 18

The invention as recited in claim 7 wherein said control station includes a register circuit for storing one of said alarm scanning signals and one of said control signals, said first signal generating means includes a first circuit connected with said register circuit and providing first alarm scanning signals thereto having addresses corresponding to said remote stations and a second circuit connected with said register circuit and providing second alarm scanning signals thereto having addresses corresponding to individual field points at said remote station, and said second signal generating means includes a third circuit connected with said register circuit and providing first control signals thereto having addresses corresponding to said remote stations and a fourth circuit connected with said register circuit and providing second control signal thereto having addresses corresponding to individual field points at said remote station.

Claim 19

The invention as recited in claim 16 wherein said first and second alarm-scanning signals and said first and second control signals are each prepared of a plurality of BITs in parallel corresponding to signal-type, function and address data, and a scanner-transmitter transmits the BITs serially to said remote stations.

Claim 20

The invention as recited in claim 17 wherein said scanner-transmitter provides a synch signal to said sequencing means at the beginning of the transmission of each of said alarm scanning and control signals, and said sequencing means is responsive to said synch signals to alternately control said first and second signal generating means.

Claim 21

The invention as recited in claim 18 wherein said sequencing means includes clock means responsive to said synch signals to general a plurality of sequential cycle signals, first, second, third and fourth transfer gates receiving said cycle signals and connected with said first, second, third and fourth circuits, respectively, and control means for said transfer gates to permit only one transfer gate to be enabled at a single time.

Claim 22

The invention as recited in claim 19 wherein said control means includes a first bistable device responsive to said synch signals, a second bistable device responsive to a first output from said first bistable device and having a first output controlling said third transfer gate and a second output controlling said fourth transfer gate, and a third bistable device having a first output controlling said first transfer gate and a second output controlling said second transfer gate in response to a second output of said first bistable device, said third bistable device having an input receiving change signals from said first and second circuits in response to the reception of said alarm signals and the completion of a scan of said groups of field points, respectively.