Forum Sensor.Community

Problems linking nodemcu v3 esp8266 chip to Network

Greetings from Sydney. Community Environmental Monitoring have set up over 95 particulate matter sensors since 2018 in NSW Australia. Recently we have been experiencing difficulty with the chip linking to the network. We commonly get the error message (see below) The site can’t be reached.
Is there something wrong with the network from the Sensor Community side, ie is it down a lot? or is it down at specific times. We noticed that over the last month there are periods when many of the already installed monitors are only working sporadically, Grafana charts as dots instead of lines.
I am not a programmer so won’t understand what to do with programming instructions. We download the firmware using windows so I assume it is the latest available. Many times have no difficulty setting up the sensor before going to a new site. In the last 3 weeks, there have been 5 occasions when a pre-tested particulate matter sensor could not be linked on-site after several hours of attempting to do so. This is very frustrating for the new sensor owner. Sydney is +11 h UTC and we normally do the set-ups between 10:00 am to 4:00 pm local time.
Kind Regards
Charlie Pierce

Processing: No network.jpg…

This symptoms are known. It is something with the number of wifi Channels, isn’t it @ricki-z ?

Hey Ricki,
Thanks for responding so fast. I am not so sure it is WIFI channels or how to check. When the access is not possible, it isn’t possible for any of the monitors in Australia. For instance today the network couldn’t be reached from 9:00 am to 1:30 local time (UTC +11). Attached is a document showing 4 of the monitors not communicating with the network when I was unable to make a connection today.
I think that the Sensor Community network was not available to us in Sydney at that time. I am wondering if it is system maintenance or something similar.

It seems I can’t paste the screen shots or the word document.

Link showing lack of access in a word document

Not sure if it is the same issue, but there was a total ‘blackout’ yesterday when I ckecked the sensor comminity map, where no sensor appeared. I didn’t check how long it lasted.

This appears to be a thing lately. A few days ago no data could be registered for about 4 hours. You can see it as a huge gap in grafana.

I checked the map again and this time it seems that there was no logging for seven hours.

What time zone are you in and what time are these shutdowns. I wonder if these are maintenance events or network problems?

My timezone is gmt+2 but it doesn’t matter.

Go to and choose any sensor, there is this 8 hour gap.

Is it during that 8 hour period you had problems?

You can check grafana for gaps at earlier dates.

Ours networks were down at the same time period but for only 4 hours.

Could be related then although personally I wouldn’t know.

My sensors and other sensors that I checked in my region also showed this line but it was just during this period. It’s not frequent as far as I know.

It happened a few days ago as well, but for a shorter period.

If you tried to access the community website, on the map, no sensor would be visible. Which means it was not an isolated case.