How do I reset an arithmetic (counter) combinator to ZERO after X amount of items have passed thru the belt? I want to do the following logic:

* Count the number of items on a belt.
* When the number of items = 41, activate an inserter and remove an item (this part is done)
* Reset the counter to ZERO.

Because Factorio treats a zero signal as 'no signal' I'm having a hard time doing this.

I tried to send a signal = signal *-1 and loop it the the counter.

I was expecting it to SUM the values and equal zero...instead it sets the value to -41

Please help.