One very nice thing about the Waveshare 3S UPS is the number of outputs. Along with 5V for the RPi, it has pins for 3.3V, 5V and 12V, making it a power source for the USB hub and for the one small relay used in the shutdown circuit, along with 2 GPIO activated relays, one for shutdown and the other for a dash light.
- rear view.JPG (4.13 MiB) Viewed 12 times
During design I added 2x 2-pin sockets for 12V and 2x 3-pin sockets for 5V and a signal line tied to GPIO. One 12V socket feeds the hub and one 5V feeds the amplifiers power on signal relay, which found a home above the fuses.
- inside 2.JPG (1.93 MiB) Viewed 12 times