Elekta Neuromag NM21283A, User Manual

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11 Miscellaneous
58 NM21283A-A
The “static” file needs to be generated for each system after any larger
maintenance operation, like changing an electronics board or a sensor.
Before saving the file, the system should be tuned, and the derivative
information should be measured. See “Measuring derivative information”
on page 54. The file can be saved normally using the
File > Save settings
menu command.
The third file loaded is deduced from the current helium level, and is
assumed to contain the nominal operating point settings. Only the operat-
ing point settings are loaded. However, these settings are not activated
automatically, so that the current operating point is not changed. If the
nominal and current operating point do differ, one can get to the nominal
one either by reloading the file explicitly or by
File > Revert to previous
op
menu command. This file should be saved after tuning the system. See
“About saving and loading settings” on page 14.
Note: Loading of the operating point parameters works differently during
the initial loading and when the parameters are loaded explicitly by issu-
ing a menu command. During the initial loading the settings of the mag-
netometer are not changed. Only the variables defining the “correct”
operating point are changed. When the settings are loaded explicitly, the
new values are sent also to the magnetometer.
The last file loaded is the preferences file, which contains the personal
preferences settings for each user. Only the parameters in class “prefer-
ences” are loaded. The preferences are saved automatically each time the
program is exited.
11.6 Updating the power-up settings
The power-up settings have been initially set at factory to values that
should enable reasonable operation of the system. Normally, you should
not change these values. Only if there is some major service operation
which results in a substantial change of the tuning parameters, the power-
up settings should be updated.
To update the power-up settings file:
1. Using a Unix shell, connect to the Janitor program at the real time
computers (assuming that the server runs on computer called
“kaptah3”):
telnet kaptah3 janitor
.
2. Give the password:
pass
<password>
3. Issue a dump command:
dump current
.
4. Make a backup copy of a file “/neuro/dacq/setup/janitor.powerup”.
Copy the newly created setup file from “/opt/HP-RT/tmp/janitor.dump”
to “/neuro/dacq/setup/janitor.powerup”.