The 150 mm High/Low Alarm Flow Meter with Optical
Sensor Switch is a noninvasive means for detection of
a HI or LOW flow. This sensor is ideal for signaling an
alarm, cutoff valve, or other device when the float
passes the detector (alarm, valve, etc. not included).
The FLSW Series helps protect your processes and
equipment from damage caused by extreme flow
rates. Its compact design and ease of operation
make it a unobtrusive, simple-to-use addition to your
This meter is perfect for OEM applications. Use
whenever maximum or minimum flow levels need to
be monitored automatically.
The FLSW Series also can be used in conjunction
with a control relay to power alternate equipment or
monitoring devices. Principle of Operation
A small, LED sensor and receiver are mounted on
one side of the flow meter. The float inside the flow
tube is detected as it passes across the beam of light.
Sensor can be used to detect float passage beyond
the setpoint of the sensor. It can also be set to monitor
float position at a specific level, signalling when float is
outside of the range of the sensor light beam.
DIP Switches are located next the the 9-pin D
connector. In order to activate the alarm sensors the
corresponding switch has to be in the “ON” position
on the DIP switch. The relay output or the buzzer or
the green LED can be separately set for momentary
or latch operation. If for example DIP Switch SW1 is
set to “ON”, when the left sensor is active, the relay
and the green LED will be energized in the latch
mode. It will remain latched until the RESET button is
pressed or external RESET TTL signal is applied.
SPECIFICATIONS Accuracy: ±2% of full scale Repeatability: 0.5% of full scale Ambient Temperature: 0 to 70°C
(32 to 158°F) Maximum Pressure: 200 psig Connections: 1/8" FNPT End Blocks: Aluminum or 316
Stainless Steel Elastomers: Buna & FKM
(Aluminum), FKM (316SS) Tube: Borosilicate Floats:Glass or 316 Stainless Steel or Tantalum Input Power: 12 Vdc, 15 Vdc
maximum, 250 mA regulated,
peak to peak maximum 100 mV Power Consumption:
Less than 200 mA Response Time: 500 milliseconds Source of Light: 65 nm, red LED Light Immunity: Pulse modulated Dry Contact Closures: 2 normally
open, and normally closed relays 91A,
30 Vdc max.) Alarm Options: High, Low or High/Low Buzzer: User configurable, momentary
or latch through DIP switch setting Reset: Reset button or remote
through “D”-through “D”-
disable relay or
buzzer Interface: 9-pin
“D”-connector Optional: 12 Vdc
tripod base Dimensions: Alarm
51.1 x 76.2 mm
(2.01 x 3.00") Enclosure #2
with Phone Plug:
30.5 x 14.2 mm (1.2 x 0.6")
All dollar amounts on this site are shown in Canadian currency.Note: Comes complete with operator's manual.
For NIST calibration for air, add suffix "-NIST AIR" to the model number, add $200 to price.
For NIST calibration for water, add suffix "-NIST WATER" to model number, add $215 to price.
For oxygen cleaning add suffix "-O2 CLEAN" to the model number, add $125 to price.
(OPTIONS SHOWN IN THIS "NOTE" ABOVE ARE PRICED IN US$)
Ordering Example: (1) FLSW3405ST aluminum rotameter with a maximum air flow 814 ml/min and a maximum water 20.4 ml/min, CAD725.00