Maximum precision in pressure regulation

Metal Work’s EB80 innovative electro-pneumatic system now features a new component: the electronic pressure regulator. Fully integrated in the solenoid valve island, this device is the result of Metal Work’s many years of experience in the development of precision electronic products. Two versions are available: “local” regulation and “series” regulation of all the elements of the EB80 island. Both of them can be inserted in either fieldbus or multi pole-controlled islands.

Metal Work’s EB80 innovative electro-pneumatic system consists of a series of products designed to control and regulate a pneumatic system, all integrated in a single expandable and reconfigurable module. All types of electro-pneumatic valves, multi-port bases, pneumatic and power supplies, modules for the management of digital and analogue input or output signals, and much more besides can be fitted into a single device. The EB80 can even be combined with drives or motion controllers to control electric motors. It is equipped with a sophisticated diagnostic system that can evaluate and report delays in response of external devices, such as pneumatic actuators, all in line with Industry 4.0 principles. There are endless possible combinations, but the greatest advantage is that they all can be obtained using a limited number of basic components, which also facilitates the job of designers who choose the EB80.  In order to achieve this objective, we devised one high-performance small-size valve unit that can cover the vast majority of applications; the space taken by the entire island is actually reduced due to the fact that the dimensions of the secondary elements – such as the end plates – have been minimised in favour of the space left for the main elements – i.e. the valves – which so provide high performance. Among the distinctive features of the EB80 are the modularity of the components and the flexibility of the system layout, which makes it really easy to insert or remove new modules, move them as required, add new functions and even change the type of control. Besides the multi-pole control version of the EB80 can control a maximum number of 38 solenoid pilots (corresponding to 38 monostable valves, 19 bistable valves or a combination of both), while the fieldbus version can control up to 128 solenoid pilots. The flow rate of standard valves is up to 800 Nl/min; high-flow valves (Patented) reaching 1,400 Nl/min can be used for increased flow rates, without changing size – which is another feature that makes the EB system really unique. 

The new electronic pressure regulator is fully integrated into the valve island

Considering the potential of the EB80 system, it is quite natural to develop new integrated components, like the new electronic pressure regulator, which allows control of a magnitude of up to a few tenths of a millibar. Metal Work has long been developing a wide range of electronic regulators, with extremely high-precision characteristics and flow rates ranging from 10 to 20,000 Nlitres/minute. The Regtronic Series, as this range of Metal Work products is called, includes miniature regulators with M5 threads for those needing space-saving solutions, medium-sized regulators with 1/8” or ¼” threads for heavy-duty use, and regulators with 2” threads for those needing high air flow rates. All the products in the Regtronic Series have excellent control characteristics: linearity within ±0.5% of full scale, hysteresis within ±0.2% of full scale, repeatability within ±0.2% of full scale and adjustable sensitivity from 10 to 300 mbar, to name just the main ones. They are all available with a display and keypad control or with an M12 connector for remote control. All models can be chosen in the version with an analogue or an IO-Link control system. The EB80 is the “brain” of the electro-pneumatic system and acts as a centralised control element of the entire pneumatic system. For applications requiring high precision in pressure regulation, the convenience of being able to integrate one or more elements capable of performing this function into the central system allows the system designer to achieve a level of flexibility that would otherwise be impossible. In this way, with an integrated device it is possible to perform the new very useful function of achieving a precise pressure regulation, in addition to all the already known EB80 features, i.e. control of directional valves, reading of digital or analogue input signals, control of digital or analogue output signals. The new element maintains all the modularity and flexibility that characterise the EB80, and can therefore be easily inserted or moved within the island; it takes the space of a 4-position base and is designed in such a way as to accommodate up to 16 elements of this type.

Two versions are available: “local” regulation and “series” regulation

From a functional point of view, the new component is available in two versions: one for “local” regulation, which controls the pressure level at the outlet located at the base of the same element, and one for a “series” regulation of all the elements of the EB80 island located to the right of the component itself. The local version is useful when precise pressure regulation is required, taken at a single outlet and usually used for a single element or a branch of the system; it also allows a good flow rate of the regulated air. The typical example of such use is when you want to regulate the pressure to a metering unit or a single actuator, with a very high degree of precision. The series version is used when you want to adjust the pressure of all the valves within the island from a certain point onwards. For example, when the first part of the island is used to control cylinders that work at a set pressure and you want to control actuators that work at a very precise pressure only from the regulator onwards; or when you want to vary the pressure dynamically, within a work cycle, by means of a command signal.

From a control point of view, both versions can be inserted in both fieldbus and multi pole-controlled islands. The fieldbus island versions are controlled via the island end plate itself, while the multi-pole island versions are equipped with their own M12 connector for power communication.

As with Metal Work’s other electronic controllers, the newcomer is available in a version with display and manual control keypad or in a version for remote control (without display). The layout of commands and the user interface follows the logic of the other elements of the EB80 family, i.e. a display, the article code and the identification symbol are visible from above (upper area compared to the bases); on the rear side of the bases, on the side opposite the pneumatic outlet, the logic diagram of the air passage inside the base itself is printed; finally, always at the back, when an M12 connector is installed, the relevant pinout diagram is also shown.

Just like the remaining part of the island, the new electronic regulator comes standard with IP65 protection rating:  in order to obtain this characteristic without losing precision, each regulator is equipped with an internal over-pressure equalisation system capable of maintaining the stated protection.