Greyline Instruments AVFM-5.0 Choice

Making the right AVFM Sensor Choice

Up or Down-looking Level Sensor...

After price - it’s the most common question:

“When should I use the separate PZ12-LP
down-looking level sensor?”

Greyline offers two sensor configurations for the AVFM:

QZ-A with Up-looking ultrasonic level and Doppler

•

velocity combined into a single-head sensor that is
installed in the bottom of a channel or pipe

QZ-B Doppler-only velocity sensor plus a separate

•

PZ12-LP down-looking ultrasonic level sensor

Choose the separate down-looking sensor when:

1. The water level is expected to drop below the 1” /

25.4 mm minimum range of the standard QZ-A
sensor.

2. The water is highly aerated.

These photos illustrate two recent AVFM applications
where separate PZ12-LP down-looking sensor was the
best choice.

Fly Creek Pump Station

Three 100 horsepower pumps discharge stormwater into
this 5 ft. Diameter concrete pipe. Maximum water level is
24” / 610 mm and maximum velocity is 8 ft/sec 2.44 m/sec.
Flow is highly turbulent and the water is aerated.

Lafarge

Final wastewater discharges from a settling lagoon through
this corrugated 24” / 610 mm steel pipe. Normal level is
10” and velocity is 7 ft/sec / 2.13 m/sec. Again the water is
turbulent and highly aerated.

In both these sample applications the QZ-A up-looking
level sensor cannot obtain a reliable echo from the water
surface so the PZ12-LP sensor is the best choice.

Visit: www.greyline.com

Fly Creek Pump Station

Lafarge Lagoon Discharge

#3 - 2002