For each of your air quality boxes, You’ll need the key components you see in the photos:
- Sensor Hub (3G GSM, GPRS 2G Mobile Cell Network, WiFi, or Ethernet)
- SPI Serial Sensor Adapter
- Alphasense OPC-N2 Particle Counter / Particulate Matter (PM) Sensor (Housing Enclosure for OPC-N2 available here)
- Tools.Valarm.net subscription ($6 per month, per Sensor Hub)
The OPC-N2 measures particles from 0.38 micron to 17 micron in diameter, like dust, pollutants and PM. We’ve found the OPC-N2 to be incredibly accurate and cost-effective for monitoring particulate matter. We were first introduced to the Alphasense OPC-N2 by 1 of our customers, the South Coast Air Quality Management District (SC-AQMD), the government agency responsible for air quality monitoring in Los Angeles, and much of Southern California.
You can see a photo on the right with the OPC-N2 installed in a weatherproof Valarm monitoring box made for AQMD. Note: The harnesses / enclosures for housing your Alphasense OPC-N2 sensors are available here. The OPC-N2 sensor communicates with Valarm and is installed in the upper left part of the BUD box in a custom made harness, and we’ve highlighted it with a big red circle in the picture here.
You can also see a the forced air intake fan on the right part of the box and an exhale vent on the bottom left. The other Alphasense air quality sensors on the bottom monitor specific gases – Ozone (O3) and Nitrogen Dioxide (NO2). See this article and step-by-step guided video tutorial for more information on how to use a Serial sensor adapter to measure specific gases from Alphasense gas sensors.
In photos there are examples of the Alphasense OPC-N2 deployed in Industrial IoT devices and boxes that are powered by solar panels and by standard mains 110V wall power.
Contact us at Info@Valarm.net if you need help making Valarm boxes for your organization.
You can also watch this video on how to make your own Industrial IoT sensor telemetry units.
The OPC-N2 is placed up top in order to mimic how particles naturally fall. An aluminum tube with a 90 degree angle comes out of the top of the box to allow fresh air with particulate matter into the OPC-N2 sensor to be counted with its laser. The OPC-N2 communicates with the Valarm system through the little black wires that connect to the SPI sensor adapter. The main difference between the Valarm boxes for solar power and mains 110V power is the solar charge controller you see at the top of the Valarm box.
Since these deployments are mobile they use 3G GSM Sensor Hubs so they can connect to the internet via mobile cell network from any location. For your deployment scenario it may be more appropriate and cost-effective for your organization to use WiFi or Ethernet sensor hubs.
GPS sensors were also added so that our customer can always know where the box is deployed and get a highly accurate timestamp that is precisely the same between all of the different air quality monitoring boxes.
How do you configure and set up your Alphasense OPC-N2 with Tools.Valarm.net??
Let’s talk about the setup and installation details. The main steps are the same as any Valarm IIoT deployment, like linking your sensor hubs to Valarm Tools Cloud, which are detailed in this HowTo Valarm video tutorial.
For setting up your OPC-N2 with your Yoctopuce SPI Serial sensor adapter, you’ll need to use specific tasks and a job file that run commands regularly asking the Alphasense OPC-N2 optical particle counter for its latest air quality measurements.
With your SPI sensor adapter connected to your computer, use virtualhub software to make this OPC-N2 .job file the default job tasks that are run whenever the sensor is started up. Once you download the Alphasense OPC-N2 job file be sure to rename it to end in .job. You’ll see the job file contains hex commands that turn on the OPC-N2 and its fan.
The job task file also contains the measure task that uses the hexadecimal 32 command to get the latest particulate matter measurements. You can see in the screenshot here the 32 hex command, which Alphasense recommends for acquiring the current readings for PM1, PM2.5, and PM10. Then the values are stored in the 1st, 2nd, and 3rd sensor values in the Yoctopuce SPI serial sensor adapter with the expect FLOAT32 argument and action at the end.
Once you’ve got your SPI sensor adapters configured and plugged into your sensor hubs, link your sensor hubs to Valarm Tools Cloud – Tools.Valarm.net.
On Tools.Valarm.net, use the Device manager to map your SPI sensor values for genericSensor 1, 2, and 3 to columns / fields. In the screenshot you’ll see we’ve mapped those 3 values, which correspond to the readings for PM1, PM2.5, and PM10, the ($1:FLOAT32) ($2:FLOAT32) and ($3:FLOAT32) from the SPI sensor job task). Use virtualhub to see the conversation between the OPC-N2 and SPI sensor adapter to verify everyone’s communicating correctly. The 3 values from the SPI sensor get mapped to the Calc 1, 2, and 3 fields on Valarm Tools Cloud.
You can map, graph, and visualize the air quality sensor data to your heart’s content. For example, here you can see a 3D Esri ArcGIS Earth visualization of a mobile air quality monitoring box with a GPS sensor and Alphasense OPC-N2.
The heights and colors of the GPS-tagged cylinders correspond to the particulate matter readings from the OPC-N2 sensor. Use the base maps dropdown menu in the upper right to change the basemap to satellite imagery, a dark gray basemap, whichever basemap is most appropriate for your Industrial IoT deployment.
You can also use the Esri ArcGIS Tools screen to map your OPC-N2 air quality sensor information on 2D maps. Use the class breaks to make choropleth maps that quickly highlight hot spots and high values of specific sensors.
Have a look at our Customer Stories page to see how customers around the world are using Valarm to remotely monitor assets in various verticals like natural resources, governments, oil & gas, agriculture, water wells, tanks, mining, chemical distribution, water resources management, and fleet vehicles, trucks, and trailers loaded up with industrial equipment and assets like pumps, vacuums, water, and tanks.
How else can you quickly and easily know what’s happening in the field?
Configure your Email alerts to be notified when remote assets measure anything outside of your custom threshold.
Also take a gander at our Web Dashboards that let you view your remote monitoring information on any device with a web browser, like your phone or tablet!
Please don’t hesitate to Contact Us at Info@Valarm.net for more information and if your organization needs to remotely monitor air quality, water, industrial vehicles, trailers, trucks, or any other assets!