Control system with predictive field device response time over a wireless network
First Claim
Patent Images
1. A control system comprising:
- a plurality of field devices;
a host computer for sending control messages to and receiving response messages from the field devices;
a wireless network having a plurality of wireless nodes that cycle between a sleep state and an active state according to a wireless network power cycle, at least one of the field devices being associated with each node; and
a gateway between the host computer and the wireless nodes;
the gateway providing the host computer, in response to a message addressed to one of the field devices, a predicted time value of when the field device will respond to the message based on the conditions comprising whether the wireless network is currently active or asleep and the amount of time left before the wireless network becomes active or goes to sleep, wherein the host computer determines whether a communication with one of the field devices has failed based on the expiration of the predicted time value.
2 Assignments
0 Petitions
Accused Products
Abstract
A host computer communicates with field devices by sending control messages and receiving response messages over a wireless network. When the host computer sends a control message to the wireless network, the host computer is provided with a predictive response time within which the field device receiving the message will respond. The wireless network cycles between a sleep state and an active state based upon a wireless network power cycle. The predicted response time is based upon the current state of the wireless network, the power cycle, and the time required for the field device to turn on, take an action (such as measuring a parameter), and generating a response message.
-
Citations
18 Claims
-
1. A control system comprising:
-
a plurality of field devices; a host computer for sending control messages to and receiving response messages from the field devices; a wireless network having a plurality of wireless nodes that cycle between a sleep state and an active state according to a wireless network power cycle, at least one of the field devices being associated with each node; and a gateway between the host computer and the wireless nodes;
the gateway providing the host computer, in response to a message addressed to one of the field devices, a predicted time value of when the field device will respond to the message based on the conditions comprising whether the wireless network is currently active or asleep and the amount of time left before the wireless network becomes active or goes to sleep, wherein the host computer determines whether a communication with one of the field devices has failed based on the expiration of the predicted time value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method of communicating between a host computer and field devices, the method comprising:
-
delivering a control message addressed to a selected field device from the host computer to a wireless network; providing to the host computer a predicted response time for a response from the selected field device based on the conditions comprising whether the wireless network is currently active or asleep and the amount of time left before the wireless network becomes active or goes to sleep wherein the host computer determines whether a communication with the selected field device has failed based on the expiration of the predicted response time;
periodically turning on the wireless nodes to transmit and receive messages;transmitting a control message to a selected field device over the wireless network to a wireless node associated with the selected field device; turning on the field device in response to a control message received that is addressed to the selected field device; generating a response message from the selected field device;
transmitting the response message over the wireless network; and
delivering the response message to the host. - View Dependent Claims (11, 12, 13)
-
-
14. A control system comprising:
-
a plurality of field devices; a host computer for sending control messages to and receiving response messages from the field devices; a plurality of wireless nodes that cycle between a sleep state and an active state according to a wireless network power cycle, at least one of the field devices being associated with each node; and a gateway between the host computer and the wireless nodes; the gateway providing the host computer, in response to a message addressed to one of the field devices, a predicted time value of when the field device will respond to the message based on the conditions comprising a field device turn-on time and a field device response time, wherein the gateway stores information regarding time required by each field device to respond to a control message after being turned on to an active state, wherein the host computer determines whether a communication with one of the field devices has failed based on the expiration of the predicted time value. - View Dependent Claims (15, 16, 17, 18)
-
Specification