Low-cost pneumatic valve terminals and digital I/O modules

Festo has launched a series of low-cost modular pneumatic valves, together with a complementary series of low-cost digital I/O modules, for its successful CPX automation platform. These latest additions further extend the platform's suitability for diverse automation control applications, bringing a new level of system configuration flexibility to OEMs and machine builders. The new MPA-L valve terminals feature sub-bases manufactured from polymer instead of metal to save cost and weight, and can be configured - and retrofitted in the field - one valve at a time. The terminals are intended primarily for cost-sensitive applications where configuration flexibility and expandability are key demands, such as in factory automation, biotechnology and the food processing industry. The new CPX-L digital I/O modules are cost-optimised, high channel density units, which are ideal for I/O intensive automation control systems.

Festo's new MPA-L low-cost modular valve terminals are based on the company's high functionality MPA-S terminals, but provide increased design granularity and a wider range of electrical connection options to simplify system integration. All MPA valve terminals, which include the MPA-S, the new MPA-L and the high flow rate MPA-F, are specifically designed to facilitate condition monitoring and diagnostics. As well as being compatible with Festo's CPX modular automation platform, which offers an exceptionally wide choice of electrical control options, MPA-L terminals are available with a number of hard-wired control schemes.

MPA-L valve terminals are especially easy to assemble. The required number of valve sub-bases are simply clamped together between two aluminium end-plates, and secured by three tie rods of the appropriate length. This arrangement results in a very robust and stable terminal, needs no special tools for assembly, and can be expanded at any time - up to 32 valve modules can be accommodated in a single block. The complete terminal can be mounted on a DIN rail, but this is not mandatory; wall and panel mount options are also available.

The valve terminal sub-base can be connected directly to a CPX terminal, providing access to a wide range of fieldbus and Industrial Ethernet products, as well as analogue and technology modules and powerful controllers such as Festo's CoDeSys-based CPX-CEC. Alternatively, the valve terminal can be hard-wired; all electrical connections are made via a multi-pin connector on one of the end-plates, which can be ordered in various IP40-rated sub-D type or flat cable configurations, or with a cage clamp for individual wires. An IP65-rated front or side entry cable connector is also available.

All MPA-L valve terminals feature generously proportioned air ducts to maximise flow and ensure reliable switching of multiple valves. Isolated ducting accommodates different pressure zones, and for high or low pressure applications, a simple selector mechanism enables the valves' pilot air supply to be derived internally or externally. Exhaust air can either be fed via a high efficiency surface silencer or ducted to an external outlet, allowing the terminal to be located in a clean environment such as a food processing area.

Festo's new CPX-L low cost digital I/O modules are designed for integration with the CPX electrical terminal - they are fully compatible with all standard CPX modules and fieldbus nodes that have polymer sub-bases - and can also be combined with MPA and VTSA valve terminals to create highly cost-effective electro-pneumatic control solutions. Featuring an IP20 rating, the modules are optimised for cabinet installation. A new type of connection block that uses novel push-in spring connections simplifies system wiring and provides a compact, high channel density interface. CPX-L modules are available with 16 digital inputs, or 8 digital inputs and 8 digital outputs; each channel offers a 3-wire connection scheme for maximum signal integrity. The modules are likely to prove especially popular with designers of control systems featuring a large number of I/O channels; compared to standard CPX digital I/O modules, they can help lower implementation costs by as much as 30 percent.