›

Battery life and download time

JorgePereiraJorgePereira
in General

Hello,

 

I am developing a project in my company where we will
have to monitor temperature, light and impact/crashes during transportations.
The equipments must log the sensor entries, and then download them at the end
of the transportation.

There are two variables very important to us. Firstly
battery life, as we will have several sensors running at the same time, it will
be impossible to change their battery in a few days cycle. We will need 30 days
battery life (60 will be preferable). Secondly the download time of the sensors
data at the end of the trip.

 

If possible, I  would like to know that in your
experience and with this conditions over 3 hours:

temperature sampling rate: 1 minute (it can go to 2 or
3 minutes)

Light sampling rate: 0.5 Hz (I think it is your
minimal, otherwise it could be lower)

Acceleration sampling rate: 10 Hz (it should be enough
to detect any collision during transportation)

 

Assuming that the loggers will be download daily, what
will be expected time for battery life (A prediction) and specially what will
be the expected download time.


 From what i see in your products metatracker or
metamotionR are the best candidates to my solution. And from what I have
understood with metamotionR I can attach a bigger mAH battery to expand battery
life right?


 My best regards and sorry for the long post 

Comments

  • EricEric
    I would recommend the MetaTracker board  as it is powered by a CR2450 battery, cheaper than the MotionR while still providing you all the features you want, and comes IP54 water-resistant mountable plastic case.  The bigger battery should easily power the board for a month given your specific use case, more if you are not continuously running all the sensors 24/7.

    Log downloads may take a few minutes but that depends on how much data you have recorded in a day.  You can use some of the on-board data processing to only record specific portions of the data rather than recording all measured values.
  • JorgePereiraJorgePereira
    Eric,

    Thank you for your support. It was very helpful.
    We intent to run those 3 sensors only during transportations. So on the rest of the day they will be off, which should give more battery life.

    as for logging, you give a good point. we are not interested in viewing all values. We are only interested to check if the temperature, light and acceleration go above/bellow tolerances during transportations. So if I understood correctly what you have said, we can code something on-board that will let us for example only log temperatures above 10ºC, or light above 100 Lx, or acceleration values  x>10, and so on. This will definetly lower the logs size.
  • EricEric
    Correct, you can setup filtering criteria on the board.
  • JorgePereiraJorgePereira
    Eric,

    Would be any problem if we replace the CR2450 for two AA batteries?
  • MattMatt
    @JorgePereira

    We do not recommend using 2xAA with the MetaTracker.  Beyond battery mounting issues, the battery level monitor is not setup for Alkaline chemistry.  Further, at around 50% discharge the AA batteries will not provide enough voltage for the ambient light sensor and extended log memory to function correctly.
This discussion has been closed.