Product introduction
1. Description of UK alphasense PM2.5 sensor OPC-N2:
PM2.5 sensors(PM2.5 detector)OPC-N2It is a lightweight device that uses an advanced optical system and precise electronic processing to provide fast and accurate particle count and particle size distribution detection.It is the second-generation product upgraded by Alphasense based on OPC-N1. It not only includes the original SPI digital signal but also adds a USB digital interface. When upgrading from N1 to N2, a built-in 16G SD card is added for data storage.The circuit and structure are more optimized, and power consumption is lower.
PM2.5 sensor OPC-N2It uses a new particle counting algorithm, integrating aerodynamics, laser detection technology, digital signal processing, and opto-mechatronics development. It features high measurement accuracy (with 16 sub-channels), stable performance, fast response time, portability, and easy operation. The low price facilitates multi-point distributed detection, forming a dense detection network and accurately providing a basis for studying air pollution conditions.
2. UK alphasensePM2.5 sensorOPC-N2 internal structure and testing principle:
Unlike traditional optical particle counters that use air pumps and sample gas filters,PM2.5 sensor OPC-N2it adopts a completely different approach. It uses a combination of a custom-designed elliptical mirror and a dual-element photodetector to create a 'virtual sensing zone' in the free space at the center of an open scattering chamber. The sensing zone and its surrounding space are illuminated by a thin ribbon-shaped laser beam. Air containing particles passes freely through the scattering chamber and can enter and exit the laser beam sensing zone, but only particles passing through the sensing zone are identified by the dual-element detector and counted/sized by the OPC electronics.
This new design uses a miniature low-power fan instead of an air pump to generate the required particle flow through the sensing zone without the need for any particle filter. This avoids the need for regular replacement of conventional pump protection filters, allowing long-term maintenance-free field operation.
3. Applications of UK alphasense PM2.5 sensor OPC-N2：
Outdoor environmental monitoring, roadside monitoring stations, industrial measurement, emission monitoring, ambient air quality monitoring systems
4. Features of UK alphasense PM2.5 sensor OPC-N2:
| Particle range | Spherical equivalent size um (based on 1.5 RI) | 0.38~17 |
| Sampling interval | Histogram period (seconds) | 1.4~10 |
| Total flow rate | L/min | 1 |
| Maximum particle count rate | Particles/second | 10000 |
| Measurement mode | mA (typical) | 175 |
| Digital interface/connection | MicroUSB | (programming), SPI (data) |
| Onboard optional | micro-SD data storage (.CSV format) | 16GB |
| Digital interface | SPI(Mode1),USB | |
| Laser classification | As enclosed housing | Class1 |
| Temperature range | °C | -10~50 |
| Humidity range | %rh (continuous) | 0~99 (non-condensing) |
The OPC-N2 electronics, combined with software applications via the SPI interface, can directly display the count and distribution of various sizes of particulate matter on a computer or Android phone, making it very easy to use.
5. Schematic diagram of PM2.5 sensor OPC-N2:
6. Measurement of PM2.5 sensor OPC-N2, particle size distribution of 5 μm alumina as displayed on PC
The above figure shows the particle size distribution detected by OPC-N2 when calibrated with standard aerosol.
