Rotork Valvekits’ Profibus-enabled switchboxes have been specified for the control of hundreds of pneumatic actuators on the new waste water treatment plant at Changi in Singapore. The switchboxes are fitted to Rotork Fluid System pneumatic actuators which – combined with a quantity of Rotork IQ electric actuators currently exceeding 2000 – represent one of the largest Profibus controlled valve actuation networks in the world. The Rotork Valvekits Circa 7000 Atex Profibus switchboxes were specified by USA and Singapore based Changi design consultants CH2M Hill. Each Circa 7000 box is capable of controlling up to 64 valve actuators on a single 2-wire loop of up to 3km length, using a directly operated 3/2 solenoid. The Circa range encompasses a broad spectrum of switchbox models, available “off the shelf” for applications ranging from general purpose to Atex certified.
