Author Topic: Battery Life  (Read 446 times)

kbrooking

  • Full Member
  • ***
  • Posts: 104
    • View Profile
Battery Life
« on: November 25, 2016, 09:20:54 pm »
Does anyone know what the typical battery life you could expect from an mc120 with a script that is checking the temp, battery voltage and reed switch every 60 seconds and transmitting to MQTT server?

Share on Facebook Share on Twitter


ajohnson

  • Newbie
  • *
  • Posts: 16
    • View Profile
Re: Battery Life
« Reply #1 on: November 26, 2016, 10:08:22 am »
What are you seeing?  I've been checking voltage and temp, and using beacons instead of MQTT, which is supposed to be similar if not better, but I saw 18 days with the new modules.  My batteries may have been crap though.  I just got a batch of Energizers in now.   Yesterday I changed my code to use SetLowPowerMode(120) in the boot function, which may or may not have been the default, and also lowered the beacon rate to 30 seconds from 10.

kbrooking

  • Full Member
  • ***
  • Posts: 104
    • View Profile
Re: Battery Life
« Reply #2 on: November 26, 2016, 11:38:18 am »
In my experiment Iím not using beacons. Iím waking up the module every 60 seconds and checking the battery voltage, temp, reed switch and sending out the data via MQTT. Looks like it dies after about 3 days.
I can try using beacons but, even then based on your results it appears it only lasts a couple weeks rather than several months. Does anyone else have any suggestions?

Nick_W

  • Full Member
  • ***
  • Posts: 215
    • View Profile
Re: Battery Life
« Reply #3 on: November 26, 2016, 11:35:38 pm »
Last I heard there is a bug in the firmware, where the numeric co-processor stops the CPU from sleeping - hence it eats batteries.

This is supposed to be resolved "soon" (that was several weeks ago).

I have stopped development on the 120 modules due to this bug, and gone back to 110's.

Hopefully "soon" is getting "sooner" every day...

kbrooking

  • Full Member
  • ***
  • Posts: 104
    • View Profile
Re: Battery Life
« Reply #4 on: November 27, 2016, 02:59:20 pm »
Thanks Nick. I was not aware of that. What sort of battery life have you seen with the 110's?

mc-John

  • Global Moderator
  • Full Member
  • *****
  • Posts: 212
    • View Profile
Re: Battery Life
« Reply #5 on: November 28, 2016, 10:20:29 am »
This has been solved and the 120 should use less than 2uA

kbrooking

  • Full Member
  • ***
  • Posts: 104
    • View Profile
Re: Battery Life
« Reply #6 on: November 28, 2016, 04:15:05 pm »
Do you have an estimate of how the battery would last if you are transmitting battery voltage and temperature to MQTT server every minute?

mc-John

  • Global Moderator
  • Full Member
  • *****
  • Posts: 212
    • View Profile
Re: Battery Life
« Reply #7 on: November 28, 2016, 06:58:35 pm »
This is depending on the settings of connection type, beacons and connection time.
Set the connection type low-power, which is the default. You can store data in the beacon and while not encrypted and is not confirmed it is by far the lowest power. The connection time is the minimum time when the device connects to the gateway even if it does not have anything to send. You lowest battery life you can accomplish is to store data in the beacon and make the connection time 15 minutes. This means that your wait time to connect to mc-Studio is between 0 and 15 minutes.

Beacon 60s Connection time 900s battery life 6.73 years
Beacon 60s Connection time 300s battery life 5.68 years
Beacon off Publish every 60s battery life 2.9 years

We have a lot of customers that measure temperature. Most measure every minute, send only based on exceptions and once every 15 minutes. That gives a battery life of more than 5 years. Some measure every 30 seconds and store the data. They then send all 30 data-points in one message and that still gives you more than 5 year battery life.

The mc-Mod110 has a much higher sleep current and the battery life is about 20 to 25% less

Hope this helps.

John

« Last Edit: November 28, 2016, 07:01:21 pm by mc-John »

kbrooking

  • Full Member
  • ***
  • Posts: 104
    • View Profile
Re: Battery Life
« Reply #8 on: November 28, 2016, 07:13:46 pm »
Thanks John. Yes this helps a lot.  ;D

Good information to know that is has been field tested with those numbers.

dmm

  • Newbie
  • *
  • Posts: 17
    • View Profile
Re: Battery Life
« Reply #9 on: December 13, 2016, 10:41:07 am »
If the secure connection is needed, so we can't use beaconing, what is the life when taking and transmitting temperature once per minute?

mc-T2

  • Administrator
  • Sr. Member
  • *****
  • Posts: 252
  • mc-Things! The opportunities are endless!
  • Location: Canada
    • View Profile
Re: Battery Life
« Reply #10 on: December 13, 2016, 11:22:15 am »
Hey davemarriot,

The estimated battery life at one temperature reading per minute (1440 readings per day, 60 per hour) and transmission of that temperature every minute (1440 transmissions per day, 60 per hour), you can expect the mcMod120 (using a standard CR2032 coin cell battery) to last approx. 2.306 years (including self-discharge of the battery).

Notes:
- This estimate cannot take into account any temperature changes which may affect the battery (low temps)
- This assumes leaving the beaconing time as default (heartbeat beacon every 10 seconds)

Hope that helps!
Need more mc-Modules, mc-Gateways or other mc-Things? Check out our product page: www.mcthings.com/products. mc-Development kits are available too!
Check out a live Dashboard using mcThings and Losant! Click here: https://goo.gl/ST43hB
Like Like x 1 View List

mc-T2

  • Administrator
  • Sr. Member
  • *****
  • Posts: 252
  • mc-Things! The opportunities are endless!
  • Location: Canada
    • View Profile
Re: Battery Life
« Reply #11 on: December 14, 2016, 04:58:14 pm »
Hello All.
Just a quick update - There was some confusion about the mcMod120 power consumption fix. The fix has been completed but it has not been released yet. Sorry for the confusion!

We will be releasing the firmware update to solve the power consumption issue within the next week or two (along with some other firmware changes). This new firmware will bring the modules down to the expected 2uA in sleep mode. Thanks for the patience and understanding on this!
Need more mc-Modules, mc-Gateways or other mc-Things? Check out our product page: www.mcthings.com/products. mc-Development kits are available too!
Check out a live Dashboard using mcThings and Losant! Click here: https://goo.gl/ST43hB