An IoT system to monitor the usage and status of a remotely placed cold water filler station.
Why It exists?
This project was developed for a construction company. Though construction sites are usually considered bad for the environment and pollution causing due to varies activities that happen during constructing a building; the company was determined to reduce the waste, make less pollution and foster an environment friendly operation at any of their construction sites.
During their internal survey they found out that the single use plastic water bottles were one of the major waste produces of their construction sites. The workers at any of their construction site relied heavily on these small single use plastic water bottle for drinking water purposes. The company saw an opportunity here to encourage the workers to stop using these bottle and instead use tap water and reusable bottles.
The Project Manager approached the team which I was part of with a concept of building a water refilling station that can be placed near the construction sites. This station would provide a filtered and cold water throughout the day to the hundreds of workers at the construction site.
After going through various approaches and types of water filtration systems, coolers and brainstorming around various designs and form factors; This the design we finalized. Its a water cooler and dispenser fitted inside a trailer. this trailer can be towed to any construction site easily with a car. I helped with the electrical design filtration, cooler system as well as the IoT system for monitoring this unit.
Though the water cooler station was deployed on the construction sites, It was essential for the workers to use those in order to really make the environmental impact hence there was a need to monitor and track the usage of this station throughout the day to observe the patterns and find ways to encourage the workers to make more use of this instead of using single use plastic bottles.
What’s inside?
Water cooler monitor is an ESP32 based IoT device. I used the “ESP32 LoRa WiFi” development board from Heltek. This board has onboard OLED screen and USBC interface along with the onboard LoRa module and an external antenna for WiFi. I developed this daughter board which basically provides interface to the sensors and powers the ESP32 directly from mains supply through a Hi-Link power module.
The Temperature Sensors
I used the DS18B20 temperature sensors which were readily available in a waterproof package with 1 meter cable. One was installed near the inlet valve and other one was placed at the output end of the cooler. These are 1-Wire based sensors that can be installed in multiples over a single wire using single GPIO pin and can be accessed by their factory programmed unique 64-bit addresses.
The Flow Sensor
The SAIER SEN-HZ43WB flow sensor was used to detect the measure the rate of flow of cold water. This sensor was placed at the outlet of the cooler.