OSI OFS-2000 Optical Flow Sensor Unit

Module Feature

OFS-2000 is Optical Scientific (OSI) patented optical scintillation gas flow sensor. It adopts non-intrusive design, the optical transmitting and receiving heads are installed on both sides of stack or duct, no components extend into gas flow channel.

It detects turbulence flicker signal of flue gas, calculates path-averaged gas velocity by DSP algorithm. It is immune to high dust, moisture and high opacity flue gas. Multiple optional versions including standard S, flare F, wet scrubber W and particulate P type. Widely matched with continuous emission monitoring system, flare gas metering and thermal oxidation process.

Working principle

Transmitter emits divergent light beam through the gas channel to receiver. Turbulence and density fluctuation in flowing gas cause light intensity scintillation.

DSP controller samples the flicker signal, calculates gas average velocity, converts measurement result to 4-20mA analog signal or serial digital data and uploads to DCS or CEMS host. Internal self-test circuit monitors optical path, power supply and hardware status.

Onboard components

Optical transmit head, optical receive head, DSP control cabinet, optical sight window, purge air fitting, terminal block for signal and power, relay alarm contact.

LED indicators

Control cabinet LED indicators for power, optical signal lock, measurement valid and system fault.

Hardware self‑diagnosis

Self-check covers optical signal loss, window contamination, power abnormality and internal DSP error. Fault state can be read via serial communication and relay output.

Programming software

OSI configuration software for velocity range setting, response time adjustment, parameter backup and fault log reading.

Electrical & Process Parameters

Model:OFS-2000 Brand:OSI Optical Scientific Device type:Optical Scintillation Gas Flow Sensor Measurement:Cross-path gas velocity Output:4~20mA, RS232 ASCII Supply:100~240V AC Certification:EPA Method14, NIST traceable Function:Non-contact average flue gas velocity measurement for stack and duct

Mechanical & Structure

Mounting:Flange mounting on stack wall Protection class:NEMA4 / NEMA4X optional Housing:Alloy explosion resistant optical head and metal control cabinet

Environmental

Operating temperature:-40℃ ~ +60℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:0~100%RH condensing allowed Certification:CE, EPA compliant Status:OSI original flow sensor spare

Installation

Install transmit and receive heads on opposite side of duct, align optical beam. Connect purge air to optical window to prevent dust and moisture pollution.

Wire AC power, 4-20mA signal cable and RS232 communication cable. Set response time and velocity range after alignment. Regularly check purge air supply and window cleanliness.

Interface

AC power terminals, 4-20mA signal terminals, RS232 serial port, alarm dry contacts, purge air inlet port.

Diagnostic

Loss of optical signal: Window fouled, optical misalignment or purge air failure.

Velocity reading drift: Purge pressure unstable or heavy particulate deposition.

System fault alarm: Control cabinet power anomaly or DSP hardware failure.

Product BriefOSI OFS-2000 optical scintillation flow sensor, non-contact cross-stack measurement, EPA Method14, 4-20mA and RS232 output, used for flare stack, CEMS and wet scrubber flue gas velocity monitoring.