ADS Environmental Services IETG FlowHawk QR 775012 A4 - Manual (Page 55)

System Overview 2-19
This method of processing data in the monitor also replaces the
need for a separate data-scrubbing process to eliminate random
pops in the data. If not identified and discarded, these outliers—
created by pipe and manhole noise, turbulent or wavy flow, a foamy
flow surface, side connections, rungs, broken pipes, or drop
connections—can make it more difficult to determine the true depth
of flow.
Pressure Depth Sensor
The optional pressure depth sensor in the Ultrasonic Depth Sensor
measures pressure depth using the same technique as the other
combo sensors, except from the top of the pipe. Since it can
provide an accurate depth only when submerged, the data from this
sensor is useful only under full-pipe or surcharge conditions. The
Ultrasonic Depth Sensor offers two options for pressure
measurement: 0 - 5 PSI (0 - 0.34 Bar) and 0 - 15 PSI (0 - 1.03 Bar).
Surface Combo Sensor
The Surface Combo Sensor with a standard 9.1-meter (30-ft) cable
(p/n 8K-CS5-V2-XX-30) mounts at the top of the pipe and
measures ultrasonic depth, surcharge pressure depth, surface
velocity, and surcharge peak velocity using four independent
sensors.