Plymovent M-1000 Control Box 120 - 575V - 0000100708 Plymovent Control Unit M-1000 controls the central fan in systems with up to 10 extractors. Must be used in conjunction with Plymovent Energy Savers or Automatic Dampers. An intelligent device that saves a lot of energy. As soon as someone starts welding an impulse is passed from the Energy Saver or Automatic Damper to the M-1000, which in turn starts the central fan. When the last person stops welding the M-1000 automatically stops the central fan. There is an adjustable over-run facility between 7 seconds and 6 minutes to remove all residual after-fume from the system. As the central fan only runs when welding is taking place, you save energy and reduce running costs. Added to this, is the low cost! M-1000 is very simple to install. Making it even more economical.