OPEN CHANNEL FLOW MONITOR SPECIFICATIONS
SCOPE: This specification covers an ultrasonic, echo-ranging
type open channel flow meter as manufactured by Greyline
Instruments, Massena, New York / Long Sault, Ontario. This
instrument shall provide for indicating, transmitting, totalizing
and data logging of the flow rate through a flume, weir, or other
primary measuring device.
- Open Channel Flow Monitor to consist of an non-contacting
ultrasonic sensor, connecting cable, and a remote
enclosure with indicating, transmitting and controlling
- Measurement accuracy shall be ±0.25% of Range or 2 mm
(0.08"), whichever is greater, and shall be
automatically temperature compensated.
- Sensor cable length shall be as required by installation,
not to exceed 500' (152 m).
- System shall have no moving parts and shall not contact
the water being measured.
- Shall include PC software program disk to determine open
channel flow calibration values for non-standard flumes
B. SENSING ELEMENT
- Sensor shall withstand accidental submersion to
10 ft (3 m) maximum.
- Sensor minimum range shall be 8"
(203.2 mm) and maximum range shall be 15 ft (4.57 m).
- Sensor shall be constructed of PVC.
- Sensor operating temperature shall be from -40°F to
150°F (-40°C to 65°C).
- Sensor shall include integral temperature sensor.
Temperature sensors requiring separate mounting and wire
runs shall not be accepted.
C. SENSOR CONNECTING CABLE
- Provide RG62AU coaxial cable 25' (7.6m) continuous
length, with waterproof, potted bond to the Sensor head.
- Extended sensor cable shall be RG62AU coaxial to a
maximum of 500' (152m). Cable shall be spliced with screw
terminal connections in manufacturer's recommended steel
NEMA4 Junction Box.
- Level and temperature signals shall be conducted on one
single coaxial cable. Separate or multiple-conductor
cables shall not be accepted.
- Sensor cable shall be installed in grounded metal
- The transmitter shall provide for field calibration to
common primary metering devices, plus allow entry of
"K" and "n" values for calibration to
nonstandard flumes, weirs or open channels.
Systems requiring calibration by Parameter
codes, BCD switches or external calibrators shall not be
- Calibration data shall be password protected and permanently stored through
power interruptions for a minimum of 12 months.
- Field calibration shall allow selection and automatic
conversion of measurement units, measurement span,
high/low flow alarm relay and flow proportional relay
- Transmitter shall permit field programmable damping to
smooth output in turbulent flow conditions, and
programmable rejection time to disregard false signals
from rain, wind, floating objects and spurious echoes.
- Transmitter operating temperature shall be from -5° to 140°F (-20° to 60°C).
Transmitter shall contain a thermostat-controlled enclosure heater for
condensation protection below 30°F (-1°C).
- Transmitter shall have an isolated 4-20mA output rated for 1000 ohm
maximum load with menu-selectable 0-5VDC alternative.
- Have a built-in 2 million point Data Logger
with USB output to flash drive or mass storage device. Include Windows software
for data log analysis, graphing and export.
- Provide two relay contacts rated 5 amp SPDT programmable for single set point alarms,
dual set point pump control, pump alternation,
temperature alarm, flow totalizer pulse and/or echo loss
- Provide a white, backlit matrix LCD
display indicating flow rate, level, relay states and 16-digit totalizer in
user-selected engineering units and with language selection including
English, French and Spanish.
- Transmitter display indicating level or flow rate, units of calibration, totalizer
and relay states shall be visible without opening cover.
- Transmitter shall be housed in a wall-mount, watertight NEMA4X (IP66)
enclosure with hinged, clear cover. Mounting hardware shall be included.
- Transmitter electronics shall be surge protected on AC power input, sensor
and 4-20mA/0-5V outputs.
- Transmitter power input shall be
100-240VAC 50-60Hz with power consumption of 4.0 Watts or less.
- The transmitter shall permit plug-in
field installation and auto-detection of optional accessories including additional control relays.
E. OPTIONAL FEATURES FOR INSERTION AS REQUIRED
- Have power input of 9-32VDC and power
consumption of less than 4.0 Watts.
- Sensor cable shall be 50 ft. (15 m) continuous length with potted bond to
the Sensor head.
- Sensor cable shall be 100 ft. (30 m) continuous length with potted bond to
the Sensor head.
- Separate length extended sensor coaxial cable shall be
extended to a
total maximum length of 500 ft (152m). Cable shall be spliced with screw
terminal connections in manufacturers recommended steel NEMA4 Junction Box.
- Sensor, connecting cable and junction boxes shall be
rated intrinsically safe to Class I,II,III, Div. I,II,
- Have a thermostat controlled enclosure heater for
Transmitter operation at temperatures below freezing.
- Have manufacturer's recommended enclosure sunscreen to
permit Transmitter mounting in direct sunlight.
- Have manufacturer's recommended Sensor sunscreen to
permit temperature-compensated Sensor mounting in direct
- Have manufacturer's recommended Panel Mount Flange
assembly for enclosure installation.
- Have 4 additional (6 total) control relays, rated 5 amp
SPDT and programmable for single set point alarms, flow proportionate pulse,
temperature alarm and/or echo loss alarm.
Open Channel Flow Monitor shall be Model OCF 5.0 as manufactured by
Greyline Instruments Inc. and shall be warranted against defects
in materials and workmanship for one year.