The iVAC MSC Pro Switch Controller for Automated Dust Control How the system works Each iVAC MSC Pro Switch can accept signals from up to 8 different Tool Plusses to form a system – more than enough for a typical workshop. If you are in a larger, multi-user workshop, the iVAC MSC Switch can be programmed to work on four different radio frequency bands - allowing you to set up to 32 different work stations.,The iVAC MSC Pro Switch Controller for Automated Dust Control How the system works Each iVAC MSC