A valve terminal is a multiple valve block (also called manifold).
They are often used where several valves are located together because a valve terminal has the advantage that the air supply (port 1) and the exhaust (ports 3 and 5) are then shared.
There are different ways to control a valve terminal:
With individual wiring, each valve has its own wiring with plus and minus (usually 24VDC).
Some valve terminals have the possibility to wire the minus (common) together and to provide the valves only with a plus.
For multipin wiring of a valve island, there is a connector connection on the valve island (usually Sub-D connector with 9, 25 or 44 connections).
You can then connect a pre-fabricated cable with plug to it, with a common minus (common) in the cable, and the valves are controlled with a single wiring (plus).
This is also a form of digital communication, but for shorter distances. The I/O link is usually used in the control cabinet to go from the controller (PLC or remote I/O) to the valve terminal. It is a cheaper solution than using a fieldbus to operate the valve terminal and is therefore very popular.
For the Festo VTUG valve terminals, the I/O link module is also the basis for the valve terminal with fieldbuses as the fieldbus modules are plugged into the I/O link module.
A fieldbus is an industrial, digital bus communication for real-time and distributed control of machines and processes. A typical process is to exchange data between the control (PLC), sensors and actuators (valve terminals).
The most common fieldbuses for valve terminals are:
- Device Net
Ebora specializes in valve terminals and is known with several brands of valve islands such as: ASCO, Bosch Rexroth, Burkert, Camozzi, Festo, Norgren
In our market sector, the common brands are Burkert and Festo.
We also did our own development in cooperation with Festo and developed the Pneumapole to make the installation of valve terminals easier and more suitable for the hygienic environment. See www.pneumapole.com