Configuring The Probe; Calibration - Water Analytics AquaMetrix AM-FOG Installation And Operation Manual

Configuring the Probe

Successful connection with the probe automatically brings up the Configuration
screen. There are four functions in the app: Measure, Diagnostics, Calibrate and
Configuration. They are accessed by clicking on the menu icon in the upper left
corner. The menu icon appears for the first time when the Configuration screen
appears.
The top of the Configuration screen allows you to personalize the probe. The
bottom of the screen allows you to set the range values for the app to be distinguish
FOG from water, FOG from air and water from sludge. There should be default
values already loaded in. They are;
1. Sludge: 0-100
2. Water: 101-1000
3. FOG: 1001-7000
4. Air: > 7001 (automatically set from the FOG upper value)
5. Temperature Compensation: 71.0
If you change the values, you must enter numbers that follow the order of
Air>FOG>Water>Sludge. If you don't, you will get an error message.
(9-14-21: NOTE: The sludge range should be higher than the water range. Also the
sludge range does nothing. This will be fixed.)
NOTE: As of this date, the probe cannot reliably distinguish water from sludge. This
will likely change in the future. To eliminate the sludge reading it is set for the very
narrow range of 0 to 100. If the probe reading yields values between 0 and 100 then
either recalibrate the Please note that the range for sludge is very narrow. That's
because we don't yet have a solid understanding of solids, so we do our best to bury
this measurement (for now!).
There is one more parameter in the bottom screen—the temperature coefficient.
This parameter adjusts the frequency values for changes resulting from different
temperatures. We have found that -71 Hz/°C is the best fit value, and it is unlikely
that you will ever change it.

Calibration

As with any sensor, two points are required to calibrate the FOG probe. The firmware
converts the frequency values from the sensors into arbitrary values, such that 0
represents the lowest value—water—and 10,000 represents the highest—air.
Calibrating the probe in water requires a container at least as deep as the probe. The 3"
diameter carrying case doubles as a reservoir for water calibration. A wider container
will give slightly better accuracy. If you have several probes in use, then a 4" PVC tube
capped at the bottom and fixed to the wall gives better accuracy and is easier to use.
For air calibration hanging the probe in air is sufficient. Keep the probe at least 2" away
from any surface.
AM-FOG Operating Manual
6
rev 0.9