Timer in a oil control unit

[gtsolid]

Good morning
I have a hydraulic unit on which I would like to install a timer 0-120 bar for making several cycles on a single-acting piston. I would like to set the duration of the periods of loading and unloading and the number of cycles.
Currently the process is manual and record the pressure manually on a gauge. The flow is really low, we have to fill a room of about 300 cm ^ 3.
i never designed an hydraulic plant, i think this i quite simple and good for me.
which components shouild i need to make a cheap plant?

 

[danw2]

Your automatation project needs an electrical solenoid valve sized for the flow rate and pressure involved, one or more timers and maybe some relay logic.

The control of the solenoid valve can be controlled with relay logic that includes one or more electronic timers (with the suitable timer logic) with an adjustable timing period, or something more sophisticated like a Programmable Logic Controller (PLC) with an HMI panel for interaction (changing the duration setting) or a 'Smart' programmable relay, both of which require a significant skill set to program and implement.

One oversight is not protecting the relay contacts from the solenoid coil's back EMF when the coil is deenergized. Make sure that for DC you put a diode or for AC you use a snubber like a 'QuenchArc' or an MOV across the relay output contacts that drive the solenoid valve.