Imp explorer project - case - grove sensor


#1

Hello friends-imp,
I am developing a project to monitor cold rooms, I want to use the Imp Explorer modules. I have used the integrated sensor HTS221, it works very well in the laboratory tests that I performed at room temperatures.

I installed the module in a cold store, but the humidity is triggered a lot, maybe the sensor becomes saturated or something happens, there is no condensate in it, or maybe the sensor needs a filter.

the temperatures will be in the range of 0-10 ° C.

Does anyone know the environmental characteristics in which the imp explorer card can operate? How long do you think the card can operate inside the camera?

This is a current graph.

I’m thinking about taking out the imp explorer module and installing a grove sensor with a length of 1.5 meters approx.

Do you know of any commercial sensor for humidity and temperature that is ready to use in the imp module?

Is there any commercial enclosure for the imp explorer?

Thanks!!!


#2

Referring to good old wikipedia and you’ll see that RH is the ratio of the partial pressure of water vapour to the equilibrium vapour pressure of water is at a given temperature.

There is usually a formula provided in the datasheets somewhere which allows you to adjust the RH values for the lower or higher temperatures.


#3

The imp001 itself is fine to -20C and the other components have an even wider range.

If you have the imp constantly powered and awake, you will see some self heating, which will bias your temperature (and hence humidity) readings. It’s best, even when AC powered to use deep sleep to minimize impact of imp power on readings.

Almost as good is to set powersave mode, which reduces idle Wi-Fi dissipation by over 90%… This is also just a one line thing.


#4

Thanks!! in the wiki found examples for the HR calculation!


#5

Thanks Hugo,
then if the imp001 works at -20C is a good one, i will use some front open enclosure with some kind of membrane/filter to maintain clean the module to some dirty environment
:smiling_imp:

I suppose that in the dev center there are example codes for deep sleep and power save.


#6

Yes, this example shows the imp taking readings and sleeping:

https://electricimp.com/docs/gettingstarted/explorer/libraries/


#7

Thanks !!!:+1:
im waiting mi new imp explorer to make this new test,
regards!


#8

Hi Hugo,
im using a server.sleepfor every 10 min,

how long an ImpExplorer module with 3 AA batteries can work??


#9

That really depends on how long you’re awake for, and what you’re doing, exactly.

If you’re only awake for a couple of seconds, I’d expect over a year with decent AAs. If you can alter your code so you only bring up wifi (eg) once per hour, but still read sensors every 10 mins and buffer them, then you can get multiple years.