2501P Remote Airborne Particle Counter
Particles Plus Remote Particle Counters
Model 2501P
0.5 – 25.0 µm @ 0.1 CFM
The Particles Plus® 2501P Remote Particle Counter is designed for continuous monitoring in cleanrooms and other controlled environments. With four particle size channels ranging from 0.5 up to 25.0 μm, these instruments deliver targeted contamination detection with real-time data collection and configurable alarms for immediate incident reporting and local visual alerts.
The compact, angled enclosures enable installation in tight locations while minimizing disruption to unidirectional airflow. These sensors are equipped with an internal vacuum source and HEPA filtered exhaust.
Built for scalability and long-term reliability, these models utilize durable laser diodes backed by a lifetime warranty and deliver exceptional zero-count performance. The 2000 Series sensors allow for efficient particle counting with specifications that exceed the ISO 21501-4 and JIS B9921 calibration standards.
With seamless connectivity, remote diagnostics, and a standardized architecture, they offer simplified integration and a lower total cost of ownership for critical monitoring applications.
| • 0.1 CFM (2.83 LPM) flow rate |
| • Long life laser diode technology for reliable performance |
| • Measures up to 4 channels of simultaneous data |
| • Accurate in high concentration environments with minimal time to zero-count |
| • Internal vacuum pump with HEPA filtered exhaust |
| • 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 warranties available. |
| Model | 2501P |
| Size Range | 0.5 μm to 25.0 μm |
| Size Channels | Factory calibrated at 0.5, 1.0, 2.5, 5.0 μm |
| Counting Efficiency | 50% @ 0.3μm; 100% for particles > 0.45 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 / 6 ft3). No fault count subtraction. |
| Calibration | NIST traceable |
| Vacuum Source | Internal vacuum pump with HEPA filter |
| Filtered Exhaust | Internal HEPA filter |
| Airflow | Internally monitored |
| Number of Channels | 4 Channels |
| Alarm | User configurable alarm LED ring |
| 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) | 3.59 x 1.83 x 5.66 in (9.1 x 4.6 x 14.3 cm) including probes and connectors |
| Weight | 1.94 lb. (0.88 kg) |
| Accessories | Wiring Connector, Operating and User Manual on USB flash drive |
| Optional Accessories | Power Supply, Remote Mounting Bracket, Isokinetic Probe, Filter Assembly, and Sample & Vacuum Tubing |
| Sample Time | 1 second to 18 hours |
| Power | 9 - 24 VDC (< 2.5 watts) |
| Operating Conditions | 41-104°F (5-40°C) / 20% to 95% non-condensing |
| Storage Conditions | 32-122°F (0-50°C) / Up to 98% non-condensing |
| Warranty | 2 Year Limited Warranty (Extended and Lifetime Warranties available) |
1- Validated by independent analysis see paper available at www.particlesplus.com/aac2022_paper
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Part Number: AS-99081 | 0.1 CFM (2.83 LPM) Part Number: AS-99002A | 100-240 VAC 50/60Hz Part Number: EE-80148 | LPM) Stainless Steel Part Number: PS-12022 |
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Bev-A-Line XX per foot Part Number: AS-99036 | Urethane per foot Part Number: AS-99018 | Line XX per foot Part Number: AS-99037 | Part Number: AS-99019 |
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Part Number: AS-99088A | Series with Pump User Manual (Printed) Part Number: MN-24028P | Series Validation Manual Part Number: MN-24034 | User Manual and PPD-9K Software (USB Key) Part Number: MN-24028 |