Lighting computer battery drain

Tuesday 29 September 2026, TRC Studio A lighting PC (TINYPC). Report from Gregbot for Ari and Greg.

Gregbot did not drain the battery. Power to the laptop's adapter dropped at 4:07 PM for 61 minutes while the plug stayed in. The computer is set to never sleep, so it ran grandMA3 on its graphics card at roughly 45 watts until the battery gave out at 5:08 PM.

What happened, minute by minute

Time	Event	Where it is recorded
8:04 AM	Woke for the day on wall power, battery at 100%	Windows power log
4:07:15 PM	Windows recorded "power source change": wall power gone, running on battery	Kernel-Power event 105
4:07 to 5:08 PM	Awake the whole time. 85% of the battery (43.7 Wh) used in 58 minutes 37 seconds	Windows battery report
5:08:34 PM	Hard power loss. Windows later logged that it had not shut down cleanly	Kernel-Power event 41, EventLog 6008
5:09:40 PM	Booted on wall power. grandMA3 started on its own at 5:16 PM	Boot record
5:18 to 5:25 PM	Charging at about 27 watts, so the adapter and outlet were working again	Three live battery readings
6:33 PM	Normal sleep (lid or power button), woke 7:53 PM at 90%	Windows power log

Could Gregbot have caused it?

The Gregbot software on this PC is the TRC fleet client: a heartbeat every five minutes, a small program that checks for jobs every five seconds, and a screen-sharing helper that only runs during a session Greg starts from the Control Room. Each way software could have played a part was checked.

Possible route	Finding
Cut the wall power	Not possible. No software can switch off the adapter or the outlet. The client contains no power commands of any kind.
Change the sleep settings so it drained instead of hibernating	Not done. The installer never touches Windows power settings. "Never sleep, never turn off the screen" is the desk's own operator setting, and it only matters once wall power is gone.
Add load and shorten the hour	Did not happen. No job and no screen-sharing session ran on this PC between 8:21 PM on the 28th and 5:18 PM on the 29th. The Gregbot process used 1.4 seconds of CPU in total.
Wake the PC from sleep	Not possible. The fleet tasks are not allowed to wake the machine, and a sleeping PC runs nothing that could be reached.
Type or click something that turned power off	Did not happen. The last screen-sharing session was 12.5 seconds at 8:21 PM on the 28th, ended by Greg.

What did cause it

Windows logged only two real losses of wall power in the last 14 days: a 9-second one on 18 September at 5:13 PM, and this 61-minute one. Since the plug did not move, the loss happened in the adapter, the barrel connector at the laptop, the cord, or the power strip or outlet it is on. Power was back by 5:09 PM when the machine was turned on again, which fits a loose connector reseating or a strip switch.

The reported battery level at the crash was about 15%, so the battery cuts out earlier than its gauge says. That is age, not software.

What to check on site

Wiggle the barrel connector at the laptop while watching the charging light. If the light flickers, the jack or the cord is the fault.
Follow the cord to its strip or outlet. If it is an energy-saving strip with a master outlet, move the adapter to an always-on outlet. If it is a smart plug, remove any schedule or automation.
Replace the adapter if the connector and strip both check out; a failing adapter that overheats and recovers matches an hour-long dropout.

Optional Windows changes (Greg's call, none applied)

Keep "never sleep" so a show cannot go dark, but turn the screen off after 5 minutes on battery and hibernate at 15% battery. Reversible in one command.
Have the fleet report when this PC is running on battery so the Control Room texts Greg. Not built yet.

Sources: Windows System event log (Kernel-Power 41, 105, 42, 107, 566; EventLog 6005, 6006, 6008), powercfg battery report, fleet door job history for lighting-pc (jobs 349 to 391), fleet responder log, fleet client source (install.ps1, fleet.js, fleet-responder.js, helper-win). Prepared by Gregbot at 8:05 PM.