AccUView LED (1/2020)
Rev 2
11
5.0 Instrument Calibration
The instrument was calibrated and tested prior to leaving the factory. Therefore, it is
possible to use the instrument directly out of the box. Under normal conditions, re-
calibration is recommended at least once every month. To get the greatest accuracy, you
may need to calibrate once per week.
Two cuvettes are supplied with the instrument so that they can be exchanged with each
other. One cuvette should always be kept clean for replacement when calibrating.
The instrument is designed to store the last reading prior to calibrating. Relay contacts are
held at the last valid condition and will not change state while the instrument is in the
calibration mode. The 4-20 mA is also held at this stored reading and will not change until
is calibration is complete. Thirty seconds after completion of the calibration the
AccUView LED will start will start taking online measurements which will be averaged
with the stored reading (depending on setting). In order to prevent disruptions in data the
operator should release the clamp to allow the sample water to flush out the calibration
water as soon as the calibration is completed.
While in the calibration mode, the instrument has a time-out feature that automatically
returns the system operation to the
AUTO
mode after a fifteen (15) minute period of
inactivity.
5.1 100 %T Calibration
Before starting the calibration procedure, be sure to turn off the instrument’s
ultrasonic cleaning option. See section 7.10 for instructions.
1.
Select the calibration function of the instrument by pressing the
MODE/EXIT
button
once. The arrow beside
CAL
will be illuminated on the display. The lower display
shows alternating
100
(indicating that the 100%T standard is requested) and
↵
. The
last reading has now been stored and the equivalent reading is being output on the 4-
20mA signal. This output will be held after the instrument returns to AUTO, allowing
time for the flow to be restarted.
2.
Close off the flow of water using the shutoff clamp.
3.
Remove the flow through cuvette, and retain for future cleaning and use.
4.
Fill the second clean cuvette with 100% T calibration fluid and reinstall the filled
cuvette tightly on the flow through unit.
5.
Wipe flow through unit dry
, install and lock in place.
6.
Press the
↵
button to start the calibration.
7.
The upper display will count down the progress of the calibration step.
8.
The instrument will return to
AUTO
mode at the end the calibration
.
9.
The shutoff clamp should now be released to restore sample flow.
10.
Do not move flow head after calibrating
.
