Jun 29, 2019

NO and NC is two different types of single acting (spring return) pneumatic actuator.

NC=Normal Close, means without air supply control, the pneumatic actuator will keep close position. The pistons position is as below picture:

NO=Normal Open, means without air supply control, the pneumatic actuator will keep open position.

The pistons position is opesite to above picture.

When ordering single acting pneumatic actuators, customers must indicate NO or NC.