The original KE3 power electronics from Hartmann & Braun can be replaced by a fully dimensionally, functionally, and terminal-compatible redesign on a true “plug and play” basis.
The VEW KE3 RED, housed in a control panel enclosure for DIN rail mounting, operates as a position controller with proportional (P) behavior by tracking the actuator position proportionally to the setpoint of the upstream controller.
The controller’s input circuit compares the specified setpoint with the feedback of the actuator’s actual position.
The difference Y_SET minus Y_ACT = ΔY controls the phase-angle firing for operation of the actuator motor, allowing the motor torque to be regulated over a wide range according to process requirements.
For a position deviation > 0.7% (1.4%), the motor delivers its rated torque.
For a position deviation < 0.7%, the torque is controlled proportionally to the position deviation.
During actuator positioning, the electronics control the motor torque so that an equilibrium is established between motor torque and load torque. As a result, the actuator is electrically held in the specified position or continuously adjusted to it.
The position control loop can be damped by connecting a tachogenerator that provides a speed-proportional signal.
The damping can be adjusted using potentiometer “y”.
For motors without a tachogenerator (M0053L … (E) M063B), the differentiated signal of the position transmitter is used.
Since the effectiveness of this differentiation is limited, its use is restricted to positioning times > 20 s.
Motors with a tachogenerator (M163LT … M1203T), however, allow shorter positioning times of < 5 s due to the adjustable damping.
The VEW KE3 RED replaces all original KE3 units, as the redesign can be configured for all motor variants via terminal bridges.
The operating capacitor required for the actuator motors is installed directly in the actuator or in a separate capacitor connection box.