The E-480 high-power amplifier/controller is specifically designed to drive high-capacitance PZT actuators. E-480 is based on a novel design employing energy-recovery technology and PWM (pulse width modulation). Instead of dissipating the reactive power in the heat sinks, it is recovered so that only the active power used by the piezo actuator has to be supplied. During discharge of the actuator, the energy not used is returned and reused to supply the amplifier.
The E-480 can output and sink a peak current of 2000 mA over a 1000-volt-wide range and features a temperature sensor input and monitoring circuit to shut down the amplifier if the PZT exceeds a maximum temperature threshold.
Because of its high output current, the E-480 can not be used to operate standard PZT translators. It is equipped with a special 8-pin connector. One of the pins is connected to the amplifier output which varies between -500 and 500 V relative to ground. The other pins are connected to fixed voltages (-500, -250, 0, 250, 500). The PZT can thus be wired for different bipolar and unipolar operating ranges. This design also allows operation of two PZT actuators in a bridge.
Standard versions can be operated in two ways:
I. Manual Open-Loop Operation:
The output voltage can be set by a 10-turn DC-offset potentiometer.
II. External Open-Loop Operation:
The output voltage is controlled by an analog signal applied to the BNC input varying over a 10-volt range. The input voltage is multiplied by the gain factor of -100 (factory settable to +100), giving an output with a 1000 V span. With the DC-offset potentiometer, the input range can be further shifted to fall anywhere in the -10 to +10 V range.
The E-480.00 allows installation of several upgrade options for enhanced versatility (see Ordering Information).
Two additional modes are possible with versions having the E-509 Sensor & Servo-Controller Module upgrade:
I. Manual Closed-Loop Operation:
Displacement of the PZTs can be set by a 10-turn DC-offset potentiometer in the range of zero to nominal displacement.
II. External Closed-Loop Operation:
Displacement of the PZT is controlled by an analog signal in the range of 0 to +10 V, applied to the BNC input. The controller is calibrated in such a way that 10 V corresponds to maximum nominal displacement and 0 V corresponds to 0 displacement. The DC-offset potentiometer can be used to add an offset voltage of 0 to 10 V to the input signal.