A local control box is used for local on/off operation of a single or double acting valve. The controls can by means of simple manual or solenoid valves to complete circuits with predefined conditions.
The control box is usually electro-hydraulic interface, solenoids will be powered remotely to open the valve and the limit switch will feed back the position of the valve (fully open or fully closed). In case a manual velocity check valve is implemented the valve can be opened manually and stay open, but after a remote shutdown it can only be opened again manually at the control box.