In electro pneumatics, electrical energy replaces pneumatic energy, the natural element for the generation and transmission of control signals that are located in control systems.

The new and/or different elements that come into play are basically constituted for the manipulation and conditioning of the voltage and current signals that must be transmitted to devices for converting electrical energy to pneumatic energy to achieve activation of the pneumatic actuators.


The set of elements that we must introduce to achieve the actuation of pneumatic actuators are basically:

Retaining elements
Mechanical limit switches.
Electro-pneumatic valves

Retaining elements
They are generally used to generate the system start signal or failing that, to make stops, either emergency or only momentary. The most common device is the push button.

electro-pneumatic buttons

Mechanical limit switches
These switches are generally used to detect the presence or absence of an element, through the mechanical contact between the switch and the element to be detected.

end of career

They are electrical devices that offer the possibility of handling on / off type control signals. They consist of a coil and a series of contacts that are normally open or closed. The principle of operation is to pass current through a coil generating a magnetic field that attracts an armature, and this in turn, switches the output contacts.

They are widely used to regulate logical sequences where high impedance loads intervene and to energize high power systems.

K1 identifies relay number one. A1 and A2 identify the relay terminals. The numbering identifies the first number with the number of contacts, while the second number (3 and 4) indicate that they are normally open contacts. For normally closed contacts the numbers 1 and 2, respectively, are used in the second digits.

pneumatic contactor relay

The core device in an electro-pneumatic circuit is the electro-pneumatic valve. This valve performs the conversion of electrical energy, coming from the relays to pneumatic energy, transmitted to the actuators or to some other pneumatic valve.

Essentially, they consist of a pneumatic valve to which a coil is attached, on which a current is passed to generate a magnetic field that, finally, will generate the commutation in the internal slide of the valve, thus generating the change of state of work of the same, modifying the service lines.

solenoid valve