The ‘DEA’ Range (previously ZBG) of Elram Electro-Hydraulic Actuators operate on a simple ‘Bi-directional motor’ principal.
As viewed from the motor fan cover end, clockwise rotation of the motor causes the actuator to extend, and anti-clockise rotation causes it to retract. when the motor is not running the actuator is stationary.
The actuator may be stopped in any position by switching off the motor.
Various hydraulic circuit configurations are available, and can be configured for ‘locked’ or ‘free to move’ conditions when the motor is running.