Factorio Forums

Attached is a save game.

Throw the power switch. This puts 50 copper plates onto the belt. The combinator at the other end is meant to count how much copper enters the final square. Only 50 enter, but it counts 90. It has something to do with the inserter pulling from the same square that's used for counting.

It's a known issue and it works like that for performance reasons.
Belts will not send correct Pulse signals when items are inserted or taken from the middle of the belt by external entities.

I will probably rewrite that part in 0.16.

Okay, thanks!