Teledyne 6650 - Fluorescence Probe - Oil in Water analysis system - Manual (Page 29)

UV-Photo-X Setup & Operation
Teledyne Analytical Instruments 21
iii. If the display is >100 counts off use the COURSE
ZERO CONTROL to bring the reading near 0000 and
then fine tune the adjustment with the FINE ZERO
CONTROL.
b) Adjusting the 4 mA level.
i. The 4 mA adjustment is located below the display.
ii. Adjust the 4 mA level until the 4-20 mA signal is in
the 4.000 ±0.164 mA range
6) Release ZRO CHK button.
7) Note the display reading.
8) If the displayed reading changed by more than 20 counts,
reinitialization of the Fluorometer may be required for
accurate process monitoring. This is especially true for
Mode 1 operation where the calibration sample is set to a
specific fluorescence level.
9) It is not recommended that the zero level be altered for
Mode 2 initialization.
5.7 Adjusting the 20 mA Level
The 20 mA level can be adjusted for both Mode 1 and Mode 2
operation using the following instructions. Although the display and 20
mA levels are interrelated in USER MODE, adjustment of the 20 mA
level will not alter the display value. For clarity the directions describe
changing the 20 mA level following a Mode 1 initialization since the
Fluorometer, will display a value easily correlated to a process variable
Causes and solution keys:
Figure 3-1 can be used to locate all the adjustment points described.
1) Immerse the probe in a process sample, preferably with a
known analyte concentration and therefore fluorescence
level.
2) Monitor the 4-20 mA signal using an appropriate meter.
3) The Fluorometer is configured in USER MODE. The
display is displaying the fluorescence intensity in arbitrary
counts.