System and method for controlling redundant communication links in networked safety systems
First Claim
1. A method for maintaining communications on a safety system network connection, comprising:
- communicating a link integrity signal indicative of a communication state on a first network communication link;
generating a control signal having characteristics corresponding to the communication state of the first network communication link;
controlling a communication link switch coupled to the first network communication link and one or more second network communication links in response to the control signal characteristics; and
switching from the first network communication link to one of the second network communication links at the communication link switch if the control signal characteristics indicate a failure affecting any one or more signals associated with the first network communication link.
1 Assignment
0 Petitions
Accused Products
Abstract
A system, apparatus, and method for maintaining communication integrity in a safety system. A link integrity signal indicative of any short circuits or open circuits in a first communication link is communicated. A control signal having characteristics corresponding to the communication state of the first communication link is generated. A communication link switch is coupled to the first communication link and one or more second communication links; this link switch being controlled in response to the control signal characteristics. If the control signal characteristics indicate that a failure affecting any one or more signals associated with the first communication link has occurred, the connection is switched to one of the second communication links.
35 Citations
43 Claims
-
1. A method for maintaining communications on a safety system network connection, comprising:
-
communicating a link integrity signal indicative of a communication state on a first network communication link;
generating a control signal having characteristics corresponding to the communication state of the first network communication link;
controlling a communication link switch coupled to the first network communication link and one or more second network communication links in response to the control signal characteristics; and
switching from the first network communication link to one of the second network communication links at the communication link switch if the control signal characteristics indicate a failure affecting any one or more signals associated with the first network communication link. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)
-
-
21. A network interface for maintaining communication integrity with at least one central processor in a safety system, comprising:
-
a communication link redundancy module including a controllable link switch for activating one of a plurality of selectable communication links between the communication link redundancy module and the central processor;
a terminal server coupled to the link switch to communicate with the central processor via the currently-activated communication link, the terminal server comprising a link signal detector to monitor a link signal indicative of a communication state of the activated communication link and to generate a control signal in response thereto; and
an interface circuit coupled to the terminal server to receive the control signal, and to generate a command to the controllable link switch to select a different one of the plurality of selectable communication links when the control signal indicates a failure of any one or more signals associated with the currently-activated communication link. - View Dependent Claims (22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 39, 40, 41, 42)
-
-
38. A safety system, comprising:
-
(a) one or more control panels, each control panel coupled to one or more safety devices to control and/or monitor the safety devices;
(b) at least one central processing system to collect data from the one or more control panels; and
(c) a network interface module coupled to the control panels and the central processing system to facilitate communication therebetween, the network interface module comprising;
(i) a communication link redundancy module including a controllable link switch for activating one of a plurality of selectable communication links between the communication link redundancy module and the central processor;
(ii) a terminal server coupled to the link switch to communicate with the central processor via the currently-activated communication link, the terminal server comprising a link signal detector to monitor a link signal indicative of a communication state of the activated communication link and to generate a control signal in response thereto; and
(iii) an interface circuit coupled to the terminal server to receive the control signal, and to generate a command to the controllable link switch to select a different one of the plurality of selectable communication links when the control signal indicates a failure of any one or more signals associated with the currently-activated communication link.
-
-
43. A network interface for maintaining communication integrity with at least one central processor in a safety system, comprising:
-
means for monitoring a link integrity signal indicative of a communication state on a first network communication link;
means for generating a control signal having characteristics corresponding to the communication state of the first network communication link as indicated by the monitored link integrity signal;
a communication link switch coupled to the first network communication link and one or more second network communication links; and
means for controlling the communication link switch, in response to the control signal characteristics, to select one of the second network communication links if the control signal characteristics indicate a failure affecting any one or more signals associated with the first network communication link.
-
Specification