New device does not show PM2.5 readings I always get a --

#1

I received my Airgradient v9 Kit last week. I think I have assembled it correctly.
I assembled the kit according to the instructions. The PM2.5 sensor was already connected to the circuit board. I put in all the rest of the sensors.

I have added all devices to the monitoring service, and all the sensors have changes in data. I have one problem: The PM2.5 sensor doesn’t seem to work or have any changes. I get either - or sometimes a 0 in the display and 0 in the website. I have tried different environments to see if I can see any changes it doesn’t change.

I opened the device to verify if the cables that connect to the blue PM sensor. I have disconnected the cable and reconnected, and have confirmed the cables are working using a multimeter. The device seems to be spinning its internal fan, but I still get no readings.

I need help to solve this problem. Could you please advise how to fix my device?

I am super happy with the rest of the device, but this is the one thing I need working so the device is perfect.

Thank you so much for your support

Nadim

#2

If you haven’t already, flash the latest firmware from the Documentation site
https://www.airgradient.com/documentation/one-v9/#firmware

#3

@nadims Yes there seems to be this behavior in low PM concentrations with some PMS sensors and we are currently looking into fixing it in the software.

If you flash a new firmware, please try the beta version 3.0.5b available from here:
Beta Firmwares

Please inform if that version works better.

#4

Setup my new v9 kit last night and having same problems as nadims.

I tested the sensor with an incense stick and all PM readings shot up so the sensor is functional but once the air clears PM2.5 goes back to 0 or - on device display+dashboard and PM0.3, PM1 & PM10 show nothing on dashboard.

Worth noting I also have an TT-AP003 Air Purifier in the room which has an included PM2.5 sensor and that is fluctuating between 5-9 µg/m3 (although I don’t know how good the sensor is).

UPDATE: I saw your reply before I posted this so just updated firmware to beta version 3.0.5b.
I see the PM polling a lot faster in the log and I’m seeing PM 0.3 counts now in both logs and dashboard.
PM2.5 shows 0 in logs and 0 on dashboard.
PM1 & PM10 show 0 in logs and nothing on dashboard.

#5

Can you please PM me your sensor serial number so that we can have a look at the data tomorrow.

#6

Do you see PM1 and PM10 above 0 in the dashboard or they just never show up?

#7

I often have 0 for PM2.5, 1, and 10, but 0.3 count always shows something. I don’t have a dedicated air purifier, but do have a 4 inch HVAC media filter with the circulation fan running.

I also have a cheap Ikea air quality sensor, and it always shows something, usually 5-13 for PM2.5 but it is a different model of sensor, and I assume that it is measuring differently, and I generally put my trust in the PMS5003 that is in the AirGradient

#8

During normal operation this is what I see -

Logs: PM1, PM2.5 & PM10 all display 0. PM0.3 displays fluctuating values.
Dashboard: PM2.5 displays 0, PM0.3 displays correct values, PM1 & PM10 display nothing (it’s just blank).

However if I wave an incense stick by the sensor for a short time I see -

Logs: All show fluctuating values.
Dashboard: All show correct values sent from device however after running the incense test some more times and comparing every post being sent from the device with the values shown on the dashboard (once they update) what I’m seeing is a little inconsistency with values updating. I’ve never witnessed PM0.3 not update correctly but I’ve witnessed PM2.5, PM1 & PM10 not update correctly (they retain their previous reading).

Yes, PM1 & PM10 do display values on the dashboard but only if they are registering above 0. I feel like they should display 0 like the PM2.5 field instead of defaulting to blank.

#9

I agree. After turning on PM1 and PM10 in the Dashboard, I also see blanks when the value should be 0

image

#10

We can reproduce this. Its an issue with the front end dashboard. Will be fixed.