Digi-Key’s Weather Platform is a self contained outdoor electronics test bench used to test and evaluate electronic projects in an outdoor environment. It evolved from the Weather Center environmental sensor monitoring project started by Digi-Key applications engineers in 2010.
Structure
The structure consists of a metal mast containing solar panels, batteries, solar charger/power supply, control box and wireless communication system. Multiple sensor and project assemblies can be attached to the metal mast and powered through the control box. The mast is mounted on the roof of Digi-Key Electronic’s headquarters building as shown in below picture.
System Description and Block Diagram
The Weather Platform is powered by three solar panels with two 12V lead acid batteries providing backup power at night and during insufficient solar output power. The battery charger / power supply keeps the 12V batteries charged and provides 5V and 12V power rails for powering wireless communication and various sensor / project assemblies attached to the mast. Both voltage and current for the solar panels, batteries, 5V power rail, and 12V power rail are monitored with data being sent over the Zigbee wireless network to the Zigbee gateway for visualization and reporting. Detailed information on the charger / power supply subsystem can be found at link .
Control Box
The control box houses the batteries, solar charger/power supply, and wireless monitoring system.
Batteries used to power the weather platform when adequate solar power is unavailable are two B B Battery BP12-12-T2 12V lead acid batteries. The solar charger / power supply uses DFRobot DFR0580 (see link for detailed implementation info).
Zigbee Wireless Communication System
A Zigbee wireless mesh network was selected for the communication system because the mesh capability provides nearly unlimited range, power consumption is low and data bandwidth is more than adequate to support the platform’s needs.
The network uses Digi Xbee3 Zigbee wireless modules. One module is configured as the coordinator and attached to a Beaglebone Green SBC to provide the Zigbee gateway function. The Zigbee gateway passes data to a JEDI One IoT application running on a Raspberry Pi.