Factorio Forums

Video: https://youtu.be/M-LJQGa6mi0

Savefile attached

When the power network runs slightly below full satisfaction (around 90%), decider combinators seem to be affected much more strongly than other entities.
In the attached save, the network shows ~90% power satisfaction, but the combinator’s own power consumption drops to about 10%.
This makes it miss input signals, even though such behavior should only occur at much lower power levels (<50%).

It looks like combinators are throttled disproportionally compared to the network’s average power satisfaction.
Combinators are often used for critical factory logic, so this behavior can easily break logic during minor power dips.

Expected:
Combinators should retain power at least proportional to global network satisfaction, so logic continues to function normally until power is genuinely low.

Thanks for the report however this is working as intended. Combinator use the secondary input priority and so other entities get power first before they do.

As far as I’ve ever known, they were not designed to be a critical part of anything.

Rseding91 wrote: Thu Oct 16, 2025 12:27 pm Thanks for the report however this is working as intended. Combinator use the secondary input priority and so other entities get power first before they do.

As far as I’ve ever known, they were not designed to be a critical part of anything.

Considering how little power combinators actually consume, would you consider giving them primary input priority instead?

In most cases, when combinators start running low on power, it breaks factory logic so severely that a reload becomes unavoidable. They’re often part of critical control circuits, so even short power dips can cause major issues. It has always been a pain in the past when a brief power spike disrupted circuitry across entire factories, so I’d really appreciate if this behavior could be reconsidered.

Given how little power a combinator consumes and that there was actually a behavior change around 2.0.65 where combinator's electric buffer was accidentaly reduced from 2x power usage down to 1x power usage, i decided to make combinators have primary power usage and increase their buffer size up to 4x power usage. That means they should be more reliable in the next release. I am not considering this change to be fixing this bug report as i was not investigating any signal losses of combinators.

Amazing. Thanks you so much for listening to the feedback!

Yeah Rseding is right that this is not a bug, It just was not obvious to me as a reporter at that point. I didn't know of the technical background of 2 underlying priorities otherwise I would have reported it as a suggestion right away.

boskid wrote: Fri Oct 17, 2025 8:43 pm Given how little power a combinator consumes and that there was actually a behavior change around 2.0.65 where combinator's electric buffer was accidentaly reduced from 2x power usage down to 1x power usage, i decided to make combinators have primary power usage and increase their buffer size up to 4x power usage. That means they should be more reliable in the next release. I am not considering this change to be fixing this bug report as i was not investigating any signal losses of combinators.

Great, from mod, there was this before 2.0 https://mods.factorio.com/mod/priority- ... rom=search and my mod for 2.0 https://mods.factorio.com/mod/ElectricPriority

You may consider including speaker too. It's important to have alert sound when there is a electric shortage for some peoples.