Below is a description of the Meshcore repeater configuration based on the nRF52840 + Wio-SX1262 with a CN3163 solar charger.
Charging solar panel (5V/10W) was used as a charging source for 18650 accu.
This project was inspired by Pawel Pieczyrak’s hints and his well done tutorial available here .
Schema:
Components used in this project:
– nRF52840 + Wio-SX1262
– MPPT CN3163 solar regulator
– 18650 accu
– 1S BMS
– 5V solar panel
– 868MHz RP-SMA Antenna with pigtail
Please note that the BMS’es P+ & P- pins are soldered to BAT+ & BAT- plate pins located directly on PCB of XIAO-nRF52840.
All parts were put into the chase and currently being tested with cloudy whether and in winter outside.
Please expect updates within the next few weeks included summary test.
After a few weeks of bad weather condition (not sun at all, clouds & very short day in PL – December) I have to say that configuration I’ve made is not the best.
Unfortunately, solar panel together with the choosen solar charger can’t manage with current demand.
This might be also due to a lot of Meshcore traffic in a place of repeater installation and many of TX packets to be retransmited.
I decided to :
– add one more 18650 accu cell
– add one more solar panel
– change the solar charger.
– antenna change on the fly .
I’ve made some solar chargers test included:
– CN3163
– CSM 40561
– CN3791
against the current providing by output pins during the constant sun light intensity.
Based on that I choosen the CN3791 suggested by Paweł.
Current setup looks as following:
With a new setup I can say that even with poor sun intensity and short day, with a lot of traffic coming into my repeater, the voltage showed within the repeater status page stays at 4V(or above) and decreases to 3.98V at the end of every day.
Please note that 10W of single solar panel suggested by the seller is hard to believe (measuring the current of shorted solar panel during the hot and sunny summer probably would provide an answer).
Antenna change has been done due to the lack of reception of packets sent by the repeater. However, it didn’t helped at all. Raising the antenna from 3 m to 7 m above ground level led to a significant improvement. That’s why I’m not really sure if it was really essential.
What is more – please note that insufficient supply voltage may cause the receiver to be deaf, even when it is ONLINE.
Jakub/SP5TOF