Process for carrying out an inspection round of nuclear installations

Process for carrying out an inspection or monitoring round of a nuclear site (5) consisting of recording in a central computer (22) connected to a radiofrequency transmitter/receiver or transceiver (24) a combination or sequence of different collection or reading points (12) grouping sensors (10) constituting the round to be performed. This sequence is copied again into a memory of a portable microcomputer (26) carried by the watchman during the round and connected to a radiofrequency transceiver (28). Each connection point (12) is validated and this validation is transmitted to the central computer (22). The sensors are checked and any abnormal condition is indicated to the central computer (22). All the checks carried out are recorded in the portable microcomputer (26) and copied again at the end of the round into a central computer (22) in such a way that they can be processed.

BACKGROUND OF THE INVENTION 
The present invention relates to a process for performing an inspection or 
monitoring round, applying more particularly to the systematic inspection 
of nuclear sites. 
The automatic operation of certain nuclear installations requires regular 
monitoring or inspection. Following a predetermined path, a watchman 
performs a round during which he collects or reads data supplied by 
sensors positioned at different points of the installation. He checks and 
optionally modifies the functional state of equipment (e.g. opening or 
closing a valve, etc.). Access to certain areas of installations can be 
difficult and even dangerous and it is also appropriate to ensure the 
safety of the watchman. At the end of the round, the results of the 
measurements performed are generally stored and used for statistical 
processing or maintenance purposes. 
French patent 2 585 145 discloses a process for monitoring an industrial 
installation. The person entrusted with the round identifies the sensors 
or equipments to be checked by reading a coded identification number 
attached to each sensor or equipment and automatically compares said 
identification number with a reference previously recorded in a reference 
or control system, the latter supplying at the end of the comparison a 
validation signal. The measurements performed during the round are 
recorded in the control system. This type of process removes 
responsibility from the operator and makes it possible to ensure the 
effective passage of the operator to the measuring points. 
The measurements carried out during the round are at the earliest analyzed 
when the operator or watchman returns to the central control station. No 
decision concerning the operation of the industrial installation can be 
taken during the round. This time lag between the measurements and their 
analysis is prejudicial to the satisfactory operation of the installation. 
Any delay in consulting the results prevents rapid, effective maintenance 
actions. 
SUMMARY OF THE INVENTION 
The aim of the present invention is to provide a process for performing a 
round which is of a very flexible nature enabling preventative maintenance 
actions to be taken. A "dialogue" between a central monitoring unit and 
the watchman makes it possible to follow the path of the latter between 
the individual measuring points and thus to ensure that the round is being 
correctly performed. This also makes it possible to indicate in real time 
any abnormal condition noted during a measurement and to very rapidly take 
the necessary steps without waiting for the watchman to return. The 
watchman has more responsibility and he may decide to carry out 
supplementary measures or equipment function state changes not initially 
provided during the definition of the course of the round. 
The watchman plays an active part in the process according to the 
invention. He is assisted in his decisions by a portable microprocessing 
means connected by a radio link to the central unit. On detecting an 
abnormal condition, he may decide to suspend his round in order to carry 
out the operations which he considers necessary, whilst keeping the 
central monitoring unit informed. 
More specifically, the present invention relates to a process for 
performing a monitoring or inspection round of a nuclear site over which 
are distributed collection or reading points grouping at least one sensor 
and at least one equipment having a certain operating state, the round 
being performed by a watchman, characterized in that it comprises: 
(a) beforehand 
(a) recording in a central computer connected to a radiofrequency 
transceiver, 
(i) a sequence or combination of collection points, sensors to be checked 
and equipments to be checked and/or whose operating state is to be 
modified, said sequence constituting the round, 
(ii) information including at least reference values, tolerance thresholds 
and assistance comments on the watchman's decision concerning the 
collection points, the sensors to be checked and the equipments to be 
checked and/or whose operating state is to be modified, 
(b) copying again the recording performed in (a) in a portable 
microcomputer connected to a radiofrequency transceiver, 
(B) during the round, 
(a) one collection point for each passage, 
(i) performing a validation affirming passage to the collection point and 
for each validation a pinpointing signal of said collection point is 
transmitted by the transmitter connected to the portable microcomputer to 
the receiver connected to the central computer and recorded in the latter, 
(ii) checking the measuring points supplying information, recording said 
information in the portable microcomputer and comparing same with 
prerecorded information concerning the measuring points in such a way as 
to detect any abnormal state, 
(iii) checking and/or modifying the operating state of the equipment, 
recording information concerning said equipment and comparing the same 
with prerecorded information concerning said equipment so as to detect any 
abnormal state, any abnormal state detection in (ii) and 
(iii) leading to the transmission by the transmitter of the portable 
microcomputer to the receiver of the central computer, 
(D) at the end of the round, the information recorded in the portable 
microcomputer is copied again into the central computer for processing. 
The validation at each collection point confirms the passage of the 
watchman, so that, via the central computer, he can be followed throughout 
his round. 
As a result of the "dialogue" between the computers enabling the watchman 
to maintain contact with the control room, any abnormal state is 
immediately passed onto the central computer and assistance or maintenance 
decisions can be taken in good time. 
The transfer of the information collected during the round into the central 
computer makes it possible to obtain a historical account for the 
individual rounds of the different measures taken.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
This industrial site 5 has not shown automatic installations, whose 
operation is checked by sensors 10 distributed over the site 5 and which 
are grouped around the collection or reading points 12. Equipments 11 
having a certain operating state are also linked with these collection 
points and can be in the form of valves, switches, etc. 
Each collection point 12 is pinpointed on the site 5 and indicated by a 
label carrying an identification bar code of the said point. In order to 
locate a collection point 12, the site 5 can e.g. be divided into levels, 
level 1 corresponding to a building 14, level 2 to part of the building 
designated as a cell 16, level 3 to part of the cell designated as a unit 
18, whereby the latter can have several collection points 12. 
In the drawing, the building 14 is subdivided into two cells 16 separated 
by a mixed line. The cells 16 are subdivided into units 18 by broken 
lines. The site 5 also has at least one control room 20 in which is 
installed at least one central computer 22 connected to a radiofrequency 
transceiver 24. The computer 22 can be of the microcomputer type. 
Various data are contained in a general file kept up to date after each 
round. This file recorded in the central computer 22 contains all the 
collection points 12 to which are allocated the identification references 
permitting their location. The file also contains the list of sensors 10 
and equipments 11 grouped around the collection points 12. These sensors 
10 and equipments 11 are indicated by identification references. This list 
in the file is completed by various informations, e.g. the type of sensor 
(thermal, electric, sensitive to radiation, sensitive to fumes) or 
equipment (valve, switch, elevator), the geographical location, the 
normally expected characteristics or values, tolerance thresholds, the 
checks to be carried out on the data collected during the rounds, the 
values obtained during the different rounds already performed, the time 
and date of these readings, the measuring units used and any other 
information making it possible to carry out an effective inspection, such 
as e.g. assistance comments on the decision regarding each of the sensors 
and equipments. 
Inter alia, this file makes it possible to display on a video monitor of a 
plan of the industrial site equipped with all the collection points, the 
sensors and equipments to be monitored. 
Before starting on his round, the watchman chooses from within the central 
file a sequence of collection points 12, sensors 10 to be checked and 
equipments to be checked and/or whose operating state is to be modified. 
This sequence is recorded in the central computer 22 and is defined by the 
performance course of the round on the site 5. Recording also takes place 
of the informations (or part thereof, but at least the reference values, 
historical values corresponding e.g. to the last five readings, tolerance 
thresholds and assistance comments on the decision) concerning the 
collection points 12, the sensors 10 and the equipments 11 to be 
monitored. 
Standard paths provided with information relating thereto are also 
available. They make it unnecessary for the watchman to redefine his 
complete path when starting out on each occasion. These standard paths can 
be modified at random. 
When the sequence or combination has been established, a theoretical time 
necessary for the path between each collection point 12 is defined. This 
time is recorded in a memory of the central computer 22 for each path 
between two collection points 12. 
Each round starts from the control room 20, where the watchman copies again 
the sequence established, as well as the informations relating thereto in 
a memory of a portable microcomputer 26 equipped with a screen associated 
with a radiofrequency transceiver 28. This microcomputer 26 is also 
equipped with a wand reader for reading a bar code 30. 
On the basis of said data, the microcomputer 26 carried during the round 
guides the watchman by indicating to him towards which collection point 12 
he should move, together with the equipments or sensors 10 to be checked. 
At each passage to a collection point 12, the watchman reads the bar code 
carrying the identification reference of the point using the wand reader 
30. This bar code reading constitutes a validation of the passage of the 
watchman to the collection point 12. The microcomputer 26 records the 
reading and allocates thereto a passage time table by means of an internal 
clock. Moreover, the microcomputer 26 displays on the screen a message 
confirming to the watchman that the collection point is indeed that 
provided in the sequence constituting the round. In the opposite case, the 
display on the screen of the portable microcomputer indicates the 
collection point normally provided. At this stage the operator has the 
choice between confirming the modification of the instruction provided by 
validating said information on the keyboard or of moving to the displayed 
collection point and carrying out again in situ an identification reading 
by reading the bar code. 
At each reading of an identification reference of the collection point, a 
pinpointing or location signal is transmitted by the transmitter 28 
connected to the portable microcomputer 26 to the receiver 24 connected to 
the central computer 22. The effect of the reception of the signal is to 
trigger an internal clock within the computer 22. If the following 
validation has not taken place when the theoretical time between two 
validations and which has been defined beforehand has elapsed, an alarm is 
given by the central computer 22. Initially said alarm can be a signal 
transmitted by the transmitter 24 associated with the central computer 22 
to the receiver 28 associated with the portable microcomputer 26. This 
signal triggers a sound and/or visual transmission or the display of a 
message on the screen of the microcomputer 26. The watchman must then 
reply by a message which he enters into the microcomputer 26 and which is 
transmitted by radiofrequency transmission to the computer 22. If no 
response is received, the computer 22 can alert an emergency team, which 
will intervene as quickly as possible when the location of the watchman 
becomes known. 
At each collection point 12, the watchman collects the informations 
supplied by the sensors 10 and records them in a memory of the portable 
microcomputer 26. He also carries out the checks and/or operating state 
changes of the equipments 11 and records information relating to said 
equipments. 
For each sensor 10 or equipment 11, the microcomputer 26 makes a comparison 
between said informations and the prerecorded values corresponding to a 
normal operation of the installations. This comparison and also the 
definition of tolerance thresholds makes it possible to detect any 
operational abnormality. 
Following each acquisition of informations concerning the sensors 10 or 
equipments 11, the watchman must carry out a validation. When the 
validated value is non-standard, via the transmitter 28, the microcomputer 
26 transmits a message to the central computer 22. As a function of the 
defective sensor 10 and the type of abnormal condition, said central 
computer alerts a maintenance team, which can operate rapidly and 
effectively. Optionally, the central computer 22 can automatically 
interrupt certain electrical or other circuits. 
When an abnormal operating state is detected, the watchman can display 
historical informations stored in the portable microcomputer 26 and which 
concern measurements performed during preceding rounds. The portable 
microcomputer 26 also displays assistance comments on the decision and, as 
a function of the particular case, the watchman can change the passage 
sequence to the collection points 12, check sensors 10 or equipments 11 
not planned during the definition of the round, or even interrupt his 
round, whilst still keeping the central computer 22 informed via the 
radiofrequency link. 
For each checked sensor 10 or equipment 11, the watchman is responsible for 
recording comments on the operation of the installations. These comments 
favour an effective preventative maintenance, because they make it 
possible to avert incidents. For example, a maintenance team alerted by 
these comments can replace a particular part before it deteriorates and in 
fact as soon as it has deficiency symptoms. 
At the end of he round, the informations read on the sensors 10 and 
contained in a memory of the portable microcomputer 26 are recorded in a 
memory of the central computer 22 in such a way that they can be processed 
there, whilst the central file is also updated. The processing can consist 
of statistics concerning a large number of rounds, evolutions of 
informations supplied by the sensors, or an analysis of variations in the 
reaadings of the sensors. If desired, a written paper report of all the 
informations can be obtained. 
The process according to the invention makes it possible to follow several 
watchmen from the same control room. The permanent link between the 
central computer and the portable microcomputer enables decisions to be 
taken rapidly and effectively. As a result of this link and the 
informations contained in the portable microcomputer, the watchman can 
analyze abnormal situations and act as a consequence thereof. He is 
responsible for his actions, whilst still being controlled by the central 
computer.