HF scientific MicroTOL Online Turbidimeter - Manual (Page 32)

MICRO TOL (5/10) 26
Rev. 4.8
8.0 Additional Features and Options
8.1 Backlit LCD
The backlit LCD allows for easier readability of the LCD display in low light or no light
conditions. The backlight is intended for continuous operation. The brightness is
adjustable from a menu in the CONFIG mode.
8.2 Ultrasonic Cleaning (Models 20055, 20056, 20063 & 20064)
This factory installed option is used to continuously clean the flow through cuvette. It is
not intended to clean cuvettes that are already dirty, or replace manual cleaning entirely.
The system will increase the time between cleanings dramatically. Please note that the
system requires the use of a special cuvette. This cuvette must be used for the system to
operate correctly.
The system works by sending an ultrasonic frequency through spring connections into a
piezo transducer bonded to the bottom of a flow through cuvette (refer to figure 6).
The system can detect that an incorrect cuvette is installed, an error has occurred in the
transducer or the transducer is not making contact with the spring connections. This error
is indicated by CLN being posted to the lower screen. Since this is an error condition, this
may affect the 4-20 mA and alarms depending in the setting of the ERLV (4-20 mA) and
if an alarm is set up to Error.
If the correct cuvette is installed, and the error is still posted, try rotating the flow through
unit slightly to improve the connection. If this fails to work, the cuvette may have to be
replaced (Catalog #24166S). The detection for this cuvette only operates in AUTO mode.
If the system is operating correctly AUTO will flash on the display.
Hint: The connection can be improved with use of a small film of an anti-oxidant compound
such as OX-GARD ™ made by GB Electrical Inc. This product is available in the
electrical section at most hardware stores.
Note: The cuvette must be completely dry before it is inserted into the sensor. If there is
any visible moisture present on the cuvette or transducer, there is a great risk of
damaging the sensor electronics and the transducer. Be sure to clean and dry the
cuvette completely just before inserting it into the sensor.
The Vapor Purge system can NOT remove large droplets of water, only residual moisture.
Note: For the Vapor Purge system to function properly, all instrument seals must be
maintained and the desiccant pack must be in good condition (no DESC display).