OSi - Model OFS-2000 - Combustion and Emissions Air Flow Sensor
- Cross stack/duct/pipe line measurement for more accurate flow readings.
- Measurement path 90° to stack; second plat-form not required – save $100K or more
- Easily replaces existing ultrasonic sensors.
- Non-interfering; nothing in flow path.
- Easy installation and optical alignment.
- Minimal upstream/downstream diameters; typically 2 & 1, not 20 & 10 like others.
- Long-term reliability: no blowers or moving parts; operates unattended - 24 / 7 / 365.
- Ultra low maintenance design.
- Rugged; designed for harsh environments.
- Built in continuous self-test diagnostics.
- Measurement unaffected by path length & media pressure, moisture & opacity.
- No flow media high temperature limits.
- Compliant with EPA 40CFR Parts 60 & 75.
- Wide versatility, NIST tested and unbeatable combination of advanced technology, high performance and proven reliability.
- Order Z-Purge Option for Class I Div I/II applications.
- Standard Control Unit is rack mount; for wall mount, order 1910-301, NEMA4 Option.
- For custom receiver cable length, order 1910-216-nnn where “nnn” is cable length in feet (max 300).
- 1910-431-nn Sight Glass w/ gaskets for media isolation (2 required, multiple models)
- 1910-420 Cast Iron Gate Valves for high temperature applications (2 required)
- 1910-804 Laptop DB9 serial communications cable
The OFS consists of DSP / multiprocessor - based control unit teamed with a set of optical transmit and receive heads which are easily installed on opposite sides of a stack, duct, vent or pipe. The OFS heads mount fully outside of the media volume behind optical windows for easy access, more accurate measurements, and greater durability. The transmit head sends a visible diverging light beam (easy to align and vibration resistant) directly across and perpendicular to the flow (although existing angled-path port can be used). The control unit processes the fluctuations seen by the receive head and displays the flow data locally and transmits it to a PC, PLC, DAS or other data collection device that accepts a serial data link and / or a 4-20 mA current loop. The control unit can be configured from either the local keypad and display, or from a laptop or portable terminal.
- Measurement Technique: Optical Scintillation (OSi Patented)
- Dynamic Range: 0.1 to40m/sec
- Accuracy (absolute): +/- 0.1 m/sec basic -or- +/- 2% of reading, whichever is greater
- Repeatability (relative): +/- 0.1 m/sec basic -or- +/-1% of reading, whichever is greater
- Long Term Drift: Less than 1% per year
- Response Time: 3 to 600 seconds, user selectable
- Automatic Calibration: 2 or 3 point; user selectable interval -or- on external command
- Sensor Health Monitoring: Continuous self-test of voltages, performance, optics, etc.
Media / Environmental
- Stack / Duct / Pipe Diameter: 0.3 to 10 m, standard -- consult factory for other ranges
- Media Temperature / Pressure / Humidity: No effect on measurement
- Media Transparency: Up to 95% opacity (OFS-2000-W is recommended for high opacity)
- Ambient Temperature / Humidity: -50 to 60 C (-58 to 140 F) / 0 -100% condensing
- Light Source: Eye-safe 670 nm visible red LED, 5 deg. divergence angle
- Sensor Heads (w/ 4'' sch.40 flange extender): 9x9x13 inches, 13 lbs. -- NEMA4 weather resistant
- Control Unit: Rack Mount Version (standard) NEMA4 Wall Mount (optional): 5 x 17 x 20 inches, 13 lbs. (for indoor use) -or- 12 x 16 x 10 inches, 15 lbs. (for outdoor / factory floor use)
- Purge Air for Heads: Normally not needed. 1-2 CFM max for some very dirty applications
- User Interface: RS-232 serial I/O and / or 4-20 mA optically isolated current loop; Also two sets of relay contacts for fault and calibration indication. Power for Transmit Head: Universal 100-240 VAC, 50/60 Hz, 12 VA (fused & surge protection)
- Power for Control Unit: Universal 100-240 VAC, 50/60 Hz, 40 VA (fused & surge protection)
- Cable between Control Unit & Receive Head: 15 foot standard; to 300 foot optional (shielded, 10 cond., 22 AWG)