Dosing, mixing, filling – the number of control applications in the process industries is steadily growing and demands high-performance positioners for process valves. Nowadays, extensive diagnostic options such as a pressure-assisted partial stroke test are vital for reliable operation. The new positioner CMSH from Festo for single-acting and double-acting actuators is therefore the perfect highly dynamic, low-wear positioning system for linear and rotary movements. Its 2-wire technology supports HART communication and condition monitoring functions.
The positioner CMSH is suitable for a broad range of applications for large and small actuators thanks to its high air flow rate. It is characterised by low internal air consumption, which makes it very energy efficient. The safety functions on the CMSH are already integrated, resulting in cost savings of up to 30%. It offers extensive integrated functions for self-monitoring and diagnostics with clear recommendations for action. This includes numerous standard diagnostic options such as position monitoring and counters for control interventions and positioner changes.
Integrated pressure sensors also enable intelligent diagnostic functions like continuous monitoring of the break-away pressure of a process valve. The positioner can be used at ambient temperatures from -40 to 80°C. This makes it the perfect positioning system for applications in the chemical industry, in mining and mineral processing as well as in the fields of energy, biotech, pharmaceuticals, cosmetics, water and bulk goods.
The positioner CMSH is user-friendly and easy to operate thanks to its large and rotatable plain-text display that can be read from various directions. The setup wizard makes it easy to commission. As part of this process, a fast or robust control mode can be selected. The device condition can be read off at a glance directly on the local display based on status feedback to NE107.
There are two ways in which it can be installed directly on the actuator: in addition to the classic installation using a mounting adapter to VDE/VDI 3845-1 with external piping, it can also be installed easily and securely with integrated air routing to VDE/VDI 3847-2 either using the connection block DADG-FM-F9-… or the pneumatic adapter of the VTOP, the pneumatic extension modules from Festo for easy and flexible integration of additional functions. The integrated air routing eliminates the need for external piping. This reduces the susceptibility to leakages to a minimum. These variants also offer the possibility of attaching additional instruments like a pilot valve, volume booster or filter regulator.
For the first time, control and safety functions are implemented within the positioner. Both functions are realised via two completely independent, separate microcontrollers for control and safety. Safety-related digital and analogue inputs enable reliable switching of the process valve in combination with the integrated pilot valve. In addition, the internal self-test guarantees the cyclical monitoring of the safety function. This makes the CMSH suitable for use in safety-related systems up to and including SIL 2. There is no need for an additional solenoid valve with external piping for the emergency shutdown (ESD) functionality. The CMSH is easy to integrate into existing, safety-related installations.