GB2124794A

GB2124794A - Monitoring system

Info

Publication number: GB2124794A
Application number: GB08222773A
Authority: GB
Inventors: Dr A Z Keller
Original assignee: TECHNOLOGY TRANSFER SERVICES L
Current assignee: TECHNOLOGY TRANSFER SERVICES L
Priority date: 1982-08-06
Filing date: 1982-08-06
Publication date: 1984-02-22

Abstract

A non intrusive reliability monitoring system comprises a micro processor 10 including a processing unit 12, a clock 16, a memory 14 and an input/output inter face 18. The inter face 18 is connectable to one or more sensors 20 located in the system under test and the processing unit is programmed to compare the input from the or each sensor with the stored programme (read only memory) and the clock and to enter into the memory any deviation of the sensed data from the stored programme. <IMAGE>

Description

SPECIFICATION Monitoring system This invention relates to a non-intrusive reliability monitoring system, and in particular to a micro-processor controlled system.

Automatically controlled systems, for example industrial plant and the like, need monitoring in order to ensure that the desired programme is in fact being followed both to ensure adequate quality of the product of such automatic system and to pin-point sources of trouble within the control systems.

Such monitoring should preferably be carried out completely independently of the automatic control systems, and should be non-intrusive, that is it should not interrupt the operation of the equipment or system from which the reliability data is to be collected in any way and should not itself constitute any hazard.

The invention seeks to provide a reliability monitoring system improved in the above respects.

According to the present invention there is provided a non-intrusive reliability monitoring system which comprises a micro processor including a processing unit, a clock, a memory and an input/output interface the interface being connectable to one or more sensors located in the system under test and the processing unit being programmed to compare input from the or each sensor with the stored programme and the clock, and enter into the memory any deviation of the sensor from the stored programme.

At suitable time intervals depending on the memory capacity of the system, and the system under test, the micro processor may be removed and the input/output interface connected to data storage means whereby the stored data in the memory will be transferred to the date storage means for subsequent analysis and evaluation.

Since the system according to the invention is set up to store in its memory only those events which do not agree with its programme, it will in effect record only misfunctions of the system under test, and therefore the memory capacity needed may be very much smaller than has hitherto been required for monitoring systems. For example, the micro processor's own random access memory may well have sufficient storage capacity without the necessity of external disk or tape storage systems. The system of the invention should preferably have an independent power source from the system under test and this may conveniently comprise a self contained battery.Currently available components enable the system of the invention to be manufactured in a very small physical size and so systems according to the invention om-be ~^ located simply and conveniently wherever needed about the system under test.

The system according to the invention may be used to monitor virtually any automatic controlled system, whether controlling indus trial machinery, production lines, boilers, hea ting/cooling systems, and so forth. The sen sors employed will be appropriate to the sys tem being monitored. For example, current flowing in the system under test can be detected by means of an inductor located adjacent to the current carrying wire forming a current transformer therewith; whether a valve is open or closed can be detected by means of an acoustic detector; temperature can be measured by means of a thermocou ple; pressure by means of a pressure trans ducer; and other non-intrusive sensors may be employed for other systems as appropriate.

After appropriate intervals, which may be periods of months, the system according to the invention may be removed and its mem ory transferred into a suitable data storage device, for example the disk storage device of a mini or micro computer. The data may then be analysed using one of the commercially available computer packages for this task.

Alternatively, rather than storing the data for subsequent analysis and evaluation, data indicating a deviation of the system being monitored from programme may be sent di rectly to a monitoring station for immediate action.

The invention will be described further, by way of example, with reference to the accom panying drawing, in which the sole figure is a block diagram of a system in accordance with the invention.

Referring to the drawing, a non-intrusive reliability monitoring system comprises a mi croprocessor generally designated 10 contain ing a central processing unit 12, random access memory 14, a clock 16, and an in put/output interface unit 1 8.

In use the micro processor 10 is connected to a series of sensors 20 arranged in the system under test as necessary to monitor the operation of that system. Data fed in from the sensors 20 through the interface 1 8 is com pared by the central processing unit 12, which contains a programme in a read-only memory (ROM). Should the sensed data at that time, as read from the clock, differ from the programmed operation of the system un der test the deviation will be recorded in the random access memory 1 4. At some suitable point the micro processor 10 may be removed from its location and, via the interface unit 1 8 connected to a suitable data storage device, for example a mini computer disc memory.

The data from the memory 14 can then be analysed and evaluated according to a com mercially available programme for this pur pose. Micro processor 10 conveniently con .;tains its own-povver sousceen -the-feffleof-r- dry cell battery and is therefore effectively self contained. Similarly the sensors 20 are of the non-intrusive variety and do not make visible connection with the system under test. Thus the operation of the monitoring system of the invention cannot in any way adversely affect the system under test.

The system of the invention provides highly reliable methods of monitoring the operation of automatic control systems.

Claims

1. A non intrusive reliability monitoring system which comprises a micro processor including a processing unit, a clock, a memory and an input/output interface, the interface being connectable to one or more sensors located in the system under test, and the processing unit being programmed to compare input from the or each sensor with a stored programme and the clock, and enter into the memory any deviation of the sensed data from the stored programme.

2. A system as claimed in claim 1 in which the memory is the random access memory in the micro processor.

3. A system according to either of claims 1 or 2 in which the programme is stored in a read only memory.

4. A system as claimed in any one of claims 1 to 3 in which the micro processor has a self contained or independent power supply from the system under test.

5. A system as claimed in any one of claims 1 to 4 in which the sensors are selected from: and inductor located adjacent to a current carrying wire forming a current transformer therewith; an accoustic detector; or a pressure transducer.

6. A system as claimed in any one of claims 1 to 5 in which a deviation between the sensed date and the programme is stored in memory.

7. A system as claimed in any one of claims 1 to 6 in which a deviation between the sensed data and the programme is sent directly to an external monitoring station.

8. A system as claimed in any one of claims 1 to 7 in which the deviations stored in the memory may be periodically transferred to a suitable data storage device for subsequent analysis.

9. A system as claimed in claim 8 in which the suitable data storage device is the disc store of a mini or micro computer.

1 0. A non intrusive reliability monitoring system substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.