Airy Technology®
Remote Particle Counters

R2301 Remote Airborne Particle Counters
0.3 – 25.0 µm @ 0.1 CFM
The R2301 Particle Counter provides a range of particle size measurement from 0.3 or 0.5 to 25.0 μm at a flow rate of 0.1 CFM (2.83 LPM). These sensors allow for efficient particle counting with specifications that exceed the ISO 21501-4 and JIS B9921 calibration standards.
These sensors have 4 fixed particle size channels and are equipped with an integral critical orifice and flow sensor to provide a stable flow rate from an external vacuum source. Integration into a building automation or facility monitoring system is easy via isolated RS-485 Modbus communication.
• 0.1 CFM (2.83 LPM) flow rate |
• Long life laser diode technology |
• Measures up to 4 channels of simultaneous data |
• Accurate in high concentration environments with minimal time to zero-count |
• Troubleshoot issues remotely from anywhere with an internet connection |
• Internal critical orifice provides precise airflow control, consistent measurements |
• Modbus RTU/ASCII data communication over isolated RS-485 |
• Complies with ISO 21501-4 and JIS B9921 standards |
• Easy to clean, lightweight stainless steel enclosure with minimal particle traps |
• Versatile mounting options |
• User configurable alarm light and LED indicators for real-time alerts |
• Seamless integration into a facility monitoring system |
• 2 Year Limited Warranty (Extended and Lifetime Warranties available) |
Model | R2301 | R2501 |
Size Range | 0.3 μm to 25 μm | 0.5 μm to 25 μm |
Size Channels | Factory calibrated at 0.3, 0.5, 1.0, and 5.0 μm | Factory calibrated at 0.5, 1.0, 2.5, and 5.0 μm |
Counting Efficiency | 50% @ 0.3μm; 100% for particles > 0.45 μm per JIS | 50% @ 0.5μm; 100% for particles > 0.75 μm per JIS |
Flow Rate | 0.1 CFM (2.83 LPM) | |
Concentration Limits | 10,000,000 particles/ft3 @ 10% coincidence (per ISO 21501-4), | |
20,000,000 particles/ft3 @ 10% coincidence (as tested and validated1) | ||
Light Source | Long life laser diode | |
Zero Count | < 1 count / 60 minutes (< 1 particles / 6ft3). No fault count subtraction. | |
Calibration | NIST traceable | |
Vacuum Requirements | External vacuum > 15” (38.1cm) of Hg | |
Airflow | Internally monitored | |
Number of Channels | 4 Channels | |
Alarm | User configurable alarm light | |
Communication Modes | MODBUS™ RTU, ASCII (over isolated RS-485) | |
Standards | ISO 21501-4 and JIS B9921 | |
Instrument Calibration | Recommended minimum once per year | |
External Surface | Stainless steel | |
Dimensions (L x W x H) | 3.5” x 1.8” x 5.2” (8.9 cm x 4.6 cm x 13.2 cm) including probes and connectors | |
Weight | 1.65 lb. (0.75 kg) | |
Accessories | Wiring Connector, Operating and User Manual on USB flash drive | |
Optional Accessories | Power Supply, Remote Mounting Bracket, Isokinetic Probe, Filter Assembly, Sample & Vacuum Tubing | |
Sample Time | 1 second to 99 hours | |
Power | 9 - 24 VDC (< 1.5 watts) | |
Operating Conditions | 41° to 104°F (5° to 40°C) / 20% to 95% non-condensing | |
Storage Conditions | 32° to 122°F (0° to 50°C) / Up to 98% non-condensing | |
Warranty | 2 Year Limited Warranty (Extended and Lifetime Warranties available) |
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Part Number: AS-99015 | Part Number: EE-80092 | Rechargeable & Removable Part Number: EE-80003A | (For EE-80003A) Part Number: AS-99005A |
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Part Number: EE-80014A | 0.1 CFM (2.83 LPM) Part Number: AS-99002 | 0.1 CFM (2.83 LPM) Part Number: AS-99002A | Connector (5 POS) Part Number: EE-79015A |
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0.1 CFM (2.83 LPM) Part Number: PS-12041 | 0.1 CFM (2.03 LPM) Part Number: PS-12070 | 0.1 CFM (2.83 LPM) Part Number: PS-12022 | 1/8 (Stainless) Part Number: PS-12005 |
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Includes 2 Rolls of Paper Part Number: AS-99011 | Single Roll Part Number: AS-99012 | Cleanroom Paper (10 Pack) Part Number: AS-99013 | 15V ~2A 100-240 VAC Part Number: EE-80127 |
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USA, Japan, Philippines, Taiwan Part Number: EE-80128 | Europe & Korea Part Number: EE-80129 | UK, Malaysia & Singapore Part Number. EE-80130 | China & Australia Part Number: EE-80131 |
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3/8" OD (1/4" ID) Part Number: AS-99019 | 3/8" OD (1/4" ID) Bev-A-Line XX Part Number: AS-99037 | Part Number: MN-24001 | 6ft (1.8m) Part Number: AS-99022 |
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User Manual (Printed) Part Number: MN-24001P | Validation Manual Part Number: MN-24002 |