Sensors - ADS TRITON+ Installation, Operation And Maintenance Manual

System Overview 2-15

Sensors

The TRITON+ flow monitor can support up to two (2) of the eight
(8) sensor types at one time to gather raw flow data. It also can
support two (2) of the same sensor type at one time, configured on
separate mounting points. Using independent measurement
techniques, ultrasonic and pressure depth sensors collect
information used to determine the depth of the flow. Velocity
sensors also use different methods to determine the average and
peak velocity of the flow. This variety of sensor options provides
the versatility of measuring the depth and velocity of the flow from
the top or bottom of the pipe and/or from within or outside of the
flow.
A sewer system's hydraulics are much more stable and uniform in
the incoming pipe than in the manhole invert or outgoing pipe.
Therefore, in installations when accurate flow-rate is desired,
mount the sensors to a stainless steel expandable ring or stainless
steel band and install the sensors in the pipe upstream from the
manhole. Installing them upstream minimizes the hydraulic effects
and erroneous data readings caused by foamy waters, flow waves,
sewer noise, non-laminar flow, and obstructions in the manhole.
If the purpose of the installation is to monitor for manhole
surcharging or overflow, and not accurate flow-rate, the sensor can
be mounted in the manhole structure. ADS recommends using the
Long Range Depth sensor for this application.