ATI
Model A15/82 Fluoride Monitor with Auto-Calibration
29
O&M Manual
Rev-G (6/10)
MAINTENANCE
The A15/82 Fluoride Monitor will generally provide unattended operation over long periods of time. With
proper care, the system should continue to provide measurements indefinitely. For reliable operation,
maintenance on the system must be done on a regular schedule. Keep in mind that preventive maintenance on
a regular schedule is much less troublesome than emergency maintenance that always seems to come at the
wrong time.
BUFFER REPLENISHMENT
The buffer solution used in the fluoride monitor must be replenished as needed. A gallon of buffer will
run the monitor for about 45 days. Larger containers of buffer may be used to extend the refill time. Buffer
should be mixed on site using the procedure found in this manual.
SENSOR MAINTENANCE
Over time, the response of the fluoride sensor can become sluggish or show excessive measurement
drift due to adsorption of impurities on the face of the sensor. To clean the sensor of fats, oils and organics,
gently rub the sensor tip with a cotton swab and ethyl alcohol. To remove inorganic residues, place the sensor tip
in a 0.1 M HCl solution for 12 hours. Another recommended way to clean the sensor is by placing toothpaste on
filter paper and rub the sensor tip gently. Once cleaning is done, rinse the face of the sensor with distilled water
and then immerse the tip in a small amount of the 100 PPM fluoride standard for about 5 minutes.
Should the fluoride system be shut down for a length of time it will be nessary to remove the sensor,
rince the sensor with de-ionized water and replace the protective cap.
PUMP MAINTNANCE
Peristaltic pump tubing should be changed every 6 months. One set of replacement tubing is supplied
with the unit and additional tube sets are available in packages of 5 (see spare parts list). If tubing wear or
leakage is noted in less than 6 months, tubing should also be replaced immediately. It is unlikely that buffer feed
tubing will require more frequent replacement, but grit in the incoming sample can cause wear on the sample
tubing, shortening the replacement interval.
Turn off power to the chemistry module prior to tubing replacement. Before replacing buffer tubing,
remove the buffer pickup tube from the buffer bottle and place the end into distilled or clean tap water. Allow the
system to run for 10 minutes to purge the buffer inside the tubing with the clean water.
Always wear eye
protection when disconnecting buffer tubing as buffer can cause stinging of the eyes.
Replacement of pump tubing is very simple with the quick loading pump heads used in this system.
Follow the procedure below for both the sample and acid pump heads. Turn off power to the chemistry module
prior to replacing pump tubes.
1. Remove the tubing clamp plate from the rear of the pump. This is done by gently pressing in on the sides of
the plate and pulling it backward. See Figure 11 for an exploded view.
2. Pull the tube retaining blocks out of the slots on the top and bottom of the pump. The tubing and blocks will
come free from the pump drive.
