Optical Scientific Inc
OFS 2000FW User’s Guide
P/N 1910-901-1
Rev. 03/28/13
1
1 OFS -2000FW OVERVIEW
1.1 Theory of Operation
Scintillation is the variation of light caused by it’s passage through pockets of air with different temperature and
density. It’s what makes the stars seem to twinkle in the night sky. OFS uses scintillation in air flow to
determine velocity. Our proven measurement technology, originally developed and patented for use in
atmospheric visibility and turbulence detecting instruments, offers unequalled response and accuracy in air
flow sensing.
This measurement is not affected by temperature and pressure.
It is completely non-intrusive to the air flow.
The basic system consists of:
Transmitter a stand-alone unit that emits an eye-safe red light beam
Receiver unit containing 2 photodetectors and signal amplifiers
Control unit that houses the DC power supply, DSP, control and user interface
Transmitter
Receiver
Control Unit
(indoor or outdoor)
Figure 1.1 OFS Basic Components
The LED in the transmitter emits a light beam which illuminates twin photodetectors in the receiver.
The received signal is amplified and sent to the Digital Signal Processor (DSP) in the Control Unit. The results
are shown on the front panel display and relayed to the customer either through a 4-20 mA current loop or
through an RS-232 interface.
The system is designed to fit standard commercial/industrial installations and to easily interface with PC, PLC,
DAS, CEM - almost any data collection device
The OFS -2000FW is a valuable tool for:
Environmental Monitoring (factory and power plant stacks, refinery flare stacks)
Process control. (gas transfer, boiler and incinerator efficiency)
Local airflow monitoring (exhaust vents, wind tunnels)
Environmental Monitoring
Process Control
Local Airflow Monitoring
Emissions-regulated industries
can use this information to
calculate volumetric flow from
their smokestacks. OFS is EPA -
compliant.
The OFS can measure the speed
of the air or gas flow in an
industrial process. The data can
be integrated into the monitoring
and control system.
OFS has been used to measure
airflow in underground tunnel
vents, roof exhaust vents, wind
tunnels and other applications
