Detecting and locating process control communication line faults from a handheld maintenance tool
AssigneeFisher-Rosemount Systems, Inc.
InventorMehul Rajeshbhai Dalal
Life of this patent
Estimating the term…
Abstract
A handheld maintenance tool operates to detect the existence of a fault in a communication line or bus, including detecting short circuit or other low impedance faults, open circuit or other high impedance faults, etc. Additionally, the handheld maintenance tool may operate to detect an approximate location of a fault within the communication line with respect to the handheld device, to thereby enable an operator or maintenance person to more easily find and repair a detected fault.
Claims20
A method of detecting the location of a fault in a process control network communication bus of a process control system of a process plant, comprising:
- generating a pulse signal on communication lines via a handheld device connected to the communication lines at a first time, the communication lines included in the process control network communication bus and to which at least one of a process controller or a field device of the process control system is connected, the at least one of the process controller or the field device installed in the process plant, and the process controller and the field device, when fully operational and communicatively coupled via the communication line, operate to control a process within the process plant;
- detecting an echo pulse signal on the communication lines at the handheld device at a second time, the echo pulse signal being a reflection of the pulse signal at the fault;
- and
- determining, via a computer processor in the handheld device, the location of the fault on the communication lines based on the detected echo pulse signal.
A handheld maintenance tool for use detecting faults in a process control network communication bus of a process control system of a process plant, comprising:
- an input/output interface configured to connect to communication lines that are included in the process control network communication bus and to which at least one of a process controller or a field device of the process control system is connected, the at least one of the process controller or the field device installed in the process plant, and the process controller and the field device, when fully operational and communicatively coupled via the communication line, operate to control a process within the process plant;
- a pulse signal generator configured to generate a pulse signal to be placed on the communication lines;
- one or more electronic signal sensors;
- a user interface;
- a processor;
- and
- a computer readable memory that stores a program to be implemented on the processor to measure an electronic signal on the communication lines in response to the pulse signal on the communication lines, to analyze the measured electronic signal to determine a location of a fault in the communication lines and to indicate the existence of the determined location of the fault to a user via the user interface.
A method of detecting a fault in a process control network of a process control system of a process plant, comprising:
- providing a first power signal on a communication line at a first amplitude level from a handheld device connected to the communication line, the communication line included in the process control network and to which at least one of a process controller or a field device of the process control system is connected, the at least one of the process controller or the field device installed in the process plant, and the process controller and the field device, when fully operational and communicatively coupled via the communication line, operate to control a process within the process plant;
- measuring a current on the communication line in response to the first power signal on the communication line at the handheld device;
- analyzing the measured current signal via a processor within the handheld device to determine the existence of a low impedance fault in the communication line in response to the first power signal;
- if a low impedance fault condition is not determined in response to the first power signal on the communication line,
- (1) providing a second power signal on the communication line at a second amplitude level higher than the first amplitude level;
- (2) measuring a further current signal on the communication line in response to the second power signal on the communication line;
- and
- (3) analyzing the measured further current signal to determine the existence of a low impedance fault in the communication line;
- and
- if a low impedance fault is determined for either of the first power signal or the second power signal, indicating the existence of a detected fault to a user via a user interface on the handheld device.
Dependencies are inferred from the claim text.