How to distinguish normally closed solenoid valve and normally open solenoid valve

The difference between normally open solenoid valve and normally closed solenoid valve

Solenoid valve according to its control mode can be generally divided into normal-open type solenoid valve and normal-closed type solenoid valve two. Special has the self-holding type solenoid valve, also called normally open normally closed type solenoid valve. What's the difference?

1、Normally open solenoid valve

Normally open solenoid valve, as its name implies that often deal with the open state of the solenoid valve, refers to the coil power off, the solenoid valve open; coil power, the solenoid valve closed.

2、Normally closed solenoid valve

Normally closed solenoid valve as its name implies that often deal with the closed state of the solenoid valve, refers to the coil power off, the solenoid valve closed.

3、The difference and choice between normally open and normally closed solenoid valves

We can choose normally closed type or normally open type according to the length of continuous working time.

• When the solenoid valve needs to be closed for a long time, and the time closed more than the time open. And the continuous open time is not very long, you can choose often closed type.
• Need a long time to open and a long time to close, to be selected from the holding type solenoid valve, that is, often open normal closed type solenoid valve.
• When the solenoid valve needs a long time to open, and the time to open more than the time to close, and continue to open the time is not very long, can choose often open.
• Or for the gas alarm system, to select the normally open type of gas emergency cut-off solenoid valve, with manual opening.
• But some need to be applied to the safety protection of the working conditions, such as furnace, kiln fire monitoring can not be selected often open, should be selected for long-term electrification.
• If it is open and close the time is equal, and also need to open for a long time or a long time to close, it is selected from the hold-up solenoid valve, also known as normally open normal closed solenoid valve.