SEC 3 runs spoilers 1 and 2. Spoiler 2 is an airbrake as well as a ground spoiler. Are you refering to the way the EFCS deals with differential inputs to the sidesticks when you refer to the voting system?
If the sidesticks are operated at the same time, the EFCS moves the controls as afunction of the algebraic sum of both inputs. Captain puts in 10 degree to the left, FO 5 degreesto the left: result 15 degree aircraft reaction to the left. If the FO went 5degrees right: result 5 degree to th e left.
SFCC are part of the EFCS. ELACs and SECs are connected to SFCCs through ARINC 429 Bus so the EFCS knows the configuration of the aircraft. SFCCs controls Blue and Green for the Slats and Yellow and Green for the Flaps. Only one SFCC needs to be working but the Slats and Flaps will run at half speed.