I've been blogging about my experience in Road Test reviewing the Ultimate Raspberry Pi Bundle. As a part of this Road Test I'm creating a Fridge/Freezer Temperature Alarm system for our local food shelf, Channel 1. You can see where this Road Test started for me here
Since my last post I've completed the Channel One Temperature Sensor, I've made the following updates:
- Changed from the charge per text SMS service Twilio to a free service called Sendhub.com
- setup my control program temp4sensor.py as a program that starts at boot time so no external display or keyboard is required
- created a project box for the unit from the shell of some old piece of electronics
- added headphone jacks for the DS18B20 temperature sensor cables. Since these cables are three wire cables I decided headphone extension cables would be an inexpensive and neat way to extend the cables as long as required for the installation.
- added an audible alarm using the Raspberry Pi 3.5mm audio out, an public domain mp3 file and an external speaker.
- added some additional try statements to handle error conditions.
Working on the project box and the headphone jacks for the temperature sensor:
The Ultimate Raspberry Pi Bundle has been a great collection of equipment to work with and even better next week I'll be demoing this custom crafted alarm system to the good people at Channel One Food Shelf. Hopefully this can be used to prevent future food loss in their aging fridge and freezer units.
I think at this point I'll create a new blog post that documents the entire process of creating the Channel One Freezer and Fridge temperature sensor.