The Ultrasonic Doppler Instrument is a compact, easy to use
system for measuring the velocity and depth of water in rivers
and streams, open drainage channels and large pipes.
It is suitable for use in a wide range of water qualities ranging
from sewerage and waste water to clean streams, potable
water, and even sea water. The instrument measures forward
and reverse flow conditions and may be programmed to
compute Flow Rate and Total Flow in pipes and open channels.
The Model 6526B consists of a combination of an ultrasonic transducer assembly (profiled to reduce flow
disturbance) and signal processing electronics. It is designed to be placed at (or near) the bottom of
the water channel for “upward looking” measurement. A single cable connects the inst rument to a 12V
dc power source.
Water velocity is measured by the ultrasonic doppler principle, which relies on suspended particles or
small air bubbles in the water to reflect the ultrasonic detector signal. The instrument will not operate
in very clean, “de-gassed” water. Water depth is gauged by a hydrostatic pressure sensor, referenced to
atomospheric pressure through the vented power and signal cable.
Water temperature is also measured. It is used to adjust for the change in velocity due to speed of
sound and is also available for logging.
21 mm/s to 4500 mm/s bi-directional
2% of measured velocity
6526-21 0 to 2m
6526-51 0 to 5m
±0.25% of calibrated lower range
-17°C to 60°C
Flow rate, totalised flow
Pipe, open channel, natural stream
Storage Memory: 100KB, CMOS RAM
programmable, 5 sec to 1 week
1200bps, instrument channel
CMOS output trigger (water sampler)
15 metre, 9 way vented, «SQL» compatible
External battery 12V dc
11.5 to 15 Vdc, 50µA standby, 200mA active, 90mA comms
Operating Temp: 0°C to 60°C water temperature
850g (2kg with 15m cable)
Versatile mounting clamp to secure a STARFLOW instrument
into a channel or a pipe. Loosening the Nylock nuts enables the
instrument to be removed for inspection. The bracket saddle
locks the instrument into its correct position and alignment.
316 stainless steel
Mounting holes: 4×M5
6526M Stainless Steel Bracket saddle with M5 Nylock nuts
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