Difference between Normally Closed and Normally Opened Solenoid Valves

Normally open solenoid valve: Normally open solenoid valve refers to the solenoid valve open when the coil is cut off; when the coil is energized, the solenoid valve closes.

Normally closed solenoid valve: Normally closed solenoid valve refers to the solenoid valve closing when the coil is cut off; when the coil is energized, the solenoid valve opens.

We can choose the normal closed type or open type according to the length of continuous working hours. Boshun Solenoid Valve Professional Research and Development Manufacturer introduces how to choose:

1. When the solenoid valve needs to be closed for a long time, and the closing time is longer than the opening time, and the continuous opening time is not very long, the normal closing type can be chosen.

Secondly, when it needs to be opened for a long time and closed for a long time, it is necessary to choose the retaining solenoid valve, that is, the normally open and closed solenoid valve.

3. When the solenoid valve needs a long time to open, and the opening time is longer than the closing time, and the continuous opening time is not very long, you can choose the normal opening type.

Fourth, or for gas alarm system, usually open gas emergency cut-off solenoid valve with manual opening should be selected.

5. However, in some situations which need to be applied to safety protection, such as furnace and kiln fire monitoring, it is impossible to open normally, and long-term power-on type should be selected.