Factorio Forums

Hi, i am not english speaker, but love this game too . Can you help me to fix my problem?
I have to backup my solar power (+ acc) with steam engines. This is common task and very many solution on this forum.
So, there are : 1 acc + decider combinator + arithmetic combinato and power swich. I use red and green wires to connect them.
1 Out acc -- signal A (for example)
2 Decider A < 10 then send 1 to power swich and arithmetc
3 Arithmetic A*(-25) and send to decider
we get simple hysteresis loop. It work fine!

but if i use on arithmetic minus (A - 25) all stop, pls help me understand WHY ?
if A=1, then A*(-25) = A - 25 (well - 26), so on out arithmetic we get same value, what the differense ?

(A * -25) will ONLY work if there is an input signal. Either you have 1 or 0:

0 * -25 = 0
1 * -25 = -25

However A - 26 will work regardless:

0 - 26 = -26
1 - 26 = -25

thanks, i can use it
.. but 1 - this is TRUE , 0 - FALSE. 0 <> FALSE
if (a<10) not true, we have no signal on exit - NOTHING. So, arithmetic get nothing (let's see GUI when mouse pointer over) and don't work. Nothing - 25 still nothing. I am a bit confusing with it. In my logic arithmetic work ONLY if decider out is true.

"Nothing" in the circuit network is not the same as Null in programming. When there is nothing for a signal it is treated as if that signal is 0.

So as far as the circuit network is concerned, [nothing] - 25 = -25

This is required behaviour, say you add 10 copper to the signal of a chest, even if that chest is completely empty you still want the +10 copper signal to go through.

I did some tests, you are right. Thank you a lot.