Advanced Instruments 4C3, User Manual

Page: 63 / 139

3. Always treat all samples uniformly before the test. Treat stan-
dards and reference solutions the same as the unknowns. Do not
intermix different tube styles.
4. To avoid contamination and evaporation, cover all samples not
immediately being tested.
5. Dirty wipers can affect the results. Replace the probe wipers
when they begin to appear dirty (about every 50 tests).
6. Use the same sample size consistently (i.e., during calibration,
testing, etc.).
7. Samples should not be re-run; use duplicate samples for repeats.
8. The first reading in any given period of operation may be slight-
ly off because of temperature conditioning or residual contami-
nation of the probe. Subsequent readings on aliquots of the same
sample should group within the specifications listed in Appendix
B.
9. If an occasional sample produces irregular results, discard obvi-
ously discrepant readings as long as the instrument has been
producing accurate readings repeatedly. Repeat the reading in
question on another aliquot.
10. To reduce the effects of evaporation, use the evaporation cover
provided in the accessory kit. Refer to the instructions on the
cover for installation.
If all instructions are followed carefully and the instrument still will
not repeat, it is possible that the probe has been damaged. The probe
may be checked as recommended in Chapter 5. If a new probe is
installed, the sample probe bin number must be reset as instructed in
Chapter 1, and the instrument must be re-calibrated as instructed in
Chapter 4. If the instrument is still not repeating, please call or write
your dealer or Advanced Instruments immediately for Hot-Line
®
ser-
vice as instructed in Chapter 5.
41
Instrument Operation