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7 GENERAL COMMENTS
7.1 SCHEDULED INSPECTIONS
There are no normally scheduled inspections required. The system is self-monitoring and will provide a chime
signal along with front panel and remote status indications (over the secure VPN Internet connection) if an out-of-
specification condition such as excessive Protected Volume (PV) magnetic fields is detected.
7.2 INDICATIONS FOR RE-CALIBRATION
A need for re-calibration is indicated by reduced system magnetic field attenuation factor or system shutdown that
is found to be due to reduced magnetic field attenuation or to oscillation in one or more axes. Causes of these
symptoms would normally be accidental misalignment of the sensing probe, changes in the site magnetic field
environment or, much less frequently, a failed system component.
7.3 RE-CALIBRATION
Recalibration is normally not required unless physical changes have been made within the site that affect the
compensation coil to probe coupling factor. For example, repositioning of the probe or large ferromagnetic object(s)
near to it. Assuming that probe clearance criteria are met (see
Section 5.1.1
), a standard setup calibration
procedure (see
Section 5.2.2
et al.) should restore normal system operational performance.
7.4 PROBE REPOSITION
For continued optimal system function, the probe must remain in its installed position and orientation. Proper system
operation after the probe is repositioned will require system recalibration.
7.5 COIL(S) REPOSITION
The coils should remain in or near their installed position and orientation. System recalibration is required after
repositioning of the coils.
7.6 SUBSYSTEM REPAIR OR REPLACEMENT
Possible need for repair or replacement of system components is shown by a persistent RED error indication
appearing on the MXA controller front panel and HTML page Status LED indicator(s), or abnormally high display
readings. Causes of system errors, whether due to component failure or external causes can, in a majority of cases,
be diagnosed remotely.
7.7 PROBE
The magnetic field sensing probe is the heart of the feedback system and is sensitive to placement and surrounding
environment. Effort must be taken to insure the isolation of the probe from sources of vibration, extraneous magnetic
fields, significant magnetic environmental alteration, or positional changes. Electronic reliability of the probe series
specified for use with the MACS/D systems is exceptional and failures are very rare. However, if the probe is
suspected as the source of a system performance issue, a replacement probe can be substituted as a quick on-site
test to determine if system operational functionality is restored. If a replacement probe is permanently installed, then
the full installation setup adjustment procedure (
Section 5.2.2
) should be followed.
