Heath Consultants GT Series - Manual (Page 122)

11-18
USER HANDBOOK
11.6.5 Calibration Required
During warm-up, if the ‘CALIBRATION REQUIRED’ flag is
displayed and an audible alarm and Red LED’s are
activated, the instrument has detected a fault in the
calibration memory during start-up and is unable to
continue without re-calibration.
Fig. 11.12 Calibration Required
The instrument must be switched off immediately. Follow
appropriate action required by your company for
calibration.
An extended period is possible, allowing the user to
continue to use the instrument for a set amount of time
after the calibration has expired. When this extended
period is over, the user will be forced to switch off the
instrument and return the instrument for calibration.