Accuracy of “triggers”


#1

In this case temperature related triggers…

I have a trigger set to email me if a temperature from a sensor falls below 18Celsius.

The sensor (DS18B20) has been giving readings of 17.nn all morning, but no alert has arrived.

Is this because the comparison is not a simple exact one and that it rounds up the sensor reading so it needs to be <17.5 to trigger


#2

the trigger when set for below 18, all value below 17.99 are considered. are you using pi or arduino?


#3

I’m using a Pi Zero W. Values have dropped well below 17.99 and no trigger has happened.

What is the sensitivity? For example, if set to 17.50 does that mean 17.49 should trigger?


#4

yes, this will triigger. what is count of your trigger counter?


#5

Where is the trigger counter? Can’t find anything in the app.

I notice that no matter what trigger value I set in the iOS apps it is always rounded up or down to the nearest whole degree?


#6

can try setting the trigger from web dashboard, also you can view the counter on the web dashboard.


#7

Thanks Shramik - I did that! The one counter has been invoked 1750+ times, the other 50+ but I only got any emails after I had gone into the web dashboard (having remembered I can’t use Firefox! :face_with_raised_eyebrow::exploding_head::weary:).

Now they are flowing every few seconds! It looks as it they only really activate when created via the web?

Unfortunately, the emails do not contain anything to indicate WHICH of your triggers generated them, even though you can give the trigger a title! It would also be good to have some means of limiting the the flow/frequency because once you know there is a problem being told every few seconds is not necessarily helpful!

It looks as if the app rounds the value it presents, even if the detail value is the one acted on.

As I’ve said before, I like Cayenne and can see the potential, but I have to say, this all has a long way to go before it is really “user ready” (I have to confess to a 35year IT career, so maybe I’m a bit picky!)

A Happy New Year - and thanks for working on New Year’s Day - it’s a holiday here.


#8

Happy new year @david3
we are aware of the issue with having multiple trigger. with pi agent you cannot solve it but if you have an arduino there is an workaround for it.Sending a lot of SMS alert and email
i will try to get it working with pi using python.


#9

Something like that would be a good idea. I do write a bit of code (Python for Pi) but my programming is a tad rusty! :rofl::cold_face:

I can see that triggers serve lots of purposes and it’s hard to design for all of them! Where do they run? In the cloud or the Pi (in my case)?.

One way of designing it might be to pass the trigger logic 3 parameters when it is set up.

  • trigger value + condition (<,>,=)
  • minimum trigger interval - to provide a flexible way to prevent flooding with messages if they are just informational, whilst reminding if nothing has been done, or to prevent multiple surplus actions. Given that IOT devices will often be remote it’s not always possible to access them to do anything!
  • trigger name (exists, but does not seem to be handed on to the email/text module) so as to be clear which one provoked the message.

Some control over the intervals at which data is collected would also be helpful I think. Not clear how that is managed at the moment, but for the thing I’m doing data every 5-10mins would be fine. I realise I could filter it after download, but it would save effort (and space) if only what is needed were collected.


#10

you dont need to program and create your own trigger engine. you just need to program (arduino/pi) in such a way that it only sends one value when the set trigger has been reached. eg. if you set trigger for temperature below 18 degree turn ON heater. then you need to create a code which only sends value below 18 once. So that it trigger the rule below 18 only once.