ups
- Three shutdowns, three causes
A storage box behind a DJI power station went down three times in two days with the battery near 95 %. The journals gave three different endings.
- The UPS said 2 minutes at 95 %
A UPS monitor took the minimum of three runtime estimates and raised low battery at 95 %. One of them was the station's time to full charge.
- The DJI went silent for four hours
A DJI Power 2000 stopped advertising over Bluetooth while the monitor served its last reading as live. Then the observer revived its own four-hour-old state.
- Enable Wake-on-LAN on Fedora with a Realtek r8169 NIC
Make a Realtek r8169 NIC on Fedora or Bazzite keep magic-packet Wake-on-LAN across shutdowns under NetworkManager, then wake the host from a MikroTik router.
- Pulling plugs on purpose
The first power-bank test passed because a second supply was hiding the failure. What each test in the UPS project could prove, and what it couldn't.
- The alert about the blackout needs the internet too
Power-cut alerts leave over an uplink the cut can take down: retries, per-channel queues, a router watchdog, and a status LED that goes dark.
- The pin template was for a different plug
Moving a Bluetooth-paired Tuya energy plug to OpenBeken without opening it, and the borrowed pin template that looked right and wasn't.
- A null battery reading cleared the low-battery alarm
Building the Go observer that serves two power stations to stock upsmon: six ways the first version could fail, and the outage test that went through.
- The DJI's grid flag is labeled charge type
A DJI Power 2000 over plaintext BLE: the documented grid byte never changed, input watts read 0 on grid, and the link drops were a 420 ms timeout.
- Twenty-five percent is a countdown
How a power station's MQTT readings should reach the machines that must shut down: a Go observer on the router that speaks NUT, as designed.