Fluke Biomedical 956A-201-M2 - Manual (Page 73)

4-1
Section 4
MAINTENANCE AND
CALIBRATION
4.1 MAINTENANCE
The 955A Area Monitoring System is designed to operate for extended periods of time with no scheduled
maintenance required. However, periodic inspections may be performed to verify system integrity and
calibration have not changed. If a problem develops, verify system calibration per section 4, or trouble
shoot the system per section 5 and the drawings in Appendix B.
If a maintenance question arises, please contact the Cardinal Health,
Radiation Management Services Customer Service Department at
(440) 248-9300 for assistance.
4.2 CALIBRATION
The 897A G-M Detector is factory calibrated on a 137 CS range. A ± 20%, 8 point NIST traceable factory
calibration performed to obtain the calibration factor and dead time correction for the detector. The
calibration factor and dead time correction (referred to as TAU) are stated on the factory calibration data
sheet, and are adjusted via setpoint numbers 5 and 2 on the 956A UDR. A field test source, P/N 848-8, is
available as an option to verify detector operation. The detector, with integral preamplifier, should be
returned to Cardinal Health, Radiation Management Services for recalibration whenever performance
degradation is noticed (i.e. detector response is not within
± 30% of the decayed source value in either the
closed or open position).
4.3 CALIBRATIONIELECTRONIC ADJUSTMENT
Table 4-1 lists the electronic adjustments for the 956A, while Table 4-2 lists electronic adjustments for the
897A detector. The procedures for making these adjustments are contained in the factory calibration and
test procedures. Note that test firmware is required to perform most of the critical adjustments. Refer to
Section 5 for a description of user-performed adjustments
.
NOTE