Manual Reset Solenoid Valves

Manual Reset or Auto Reset?

The majority of solenoid valves are of the Auto Reset type which means that the valve will change state without external operator influence which is ideal for process automation.

There are occasions where safety requires that a valve cannot be remotely operated by a control system without an additional human input directly at the valve. This is what is known as Manual Reset. To cause the valve to change from its rest state, the coil must be energised and the lever or knob pulled to the fully open position. If the valve is energised without the manual intervention, it will not open.

There are other forms of manual reset with different operating characteristics.

Manual Latching is where the valve is opened by hand and will not close until the coil is energised. This is also known as electrical trip or electrical release.

Automatic Latching Lever is almost the opposite of this in that the valve is energised to change state which releases the lever. The lever falls due to gravity and holds the valve in the open position regardless of whether the coil is energised on not. The lever has to be manually operated in order to return the valve to the closed rest position.

Types of Manual Reset Solenoid Valves