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6 Start-Up and Operation
36 Version: 1.0.0 PZ265E PL0xx/PDxxx Piezo Actuator
6.2.1 Overview of Limiting Factors
Limiting factors for the operation of the piezo actuator:

Resonant frequency:
The resonant frequency of the piezo actuator serves as a basis for calculating the operating
frequency, which must not exceed one third of the resonant frequency. The resonant
frequencies given in the data tables (p. 49) apply to operation of the piezo actuator when it
is unloaded and not clamped on both sides. In an arrangement with unilateral clamping, the
value has to be divided in half.
For
loaded piezo actuators that are clamped on one side, see "Calculating the Maximum
Operating Frequency of the Loaded Piezo Actuator" (p. 37).

Maximum compressive/tensile stress capacity (p. 52):
The mass of the load to be moved, the preload, and the operating frequency of the piezo
actuator must be selected so that the dynamic forces occurring during operation do not
exceed the maximum tensile/compressive stress capacity of the piezo actuator. See
"Calculating the Forces that Occur During Dynamic Operation" (p. 38).

Maximum permissible operating temperature of the piezo actuator (p. 53):
The greater the operating frequency, the operating voltage (peak-to-peak), and the
capacitance of the piezo actuator, the greater the thermal power generated in the piezo
actuator. The operating frequency, operating voltage and operating time must be selected
so that the maximum permissible operating temperature of the piezo actuator is not
exceeded. For the maximum permissible operating frequency without cooling, see column B
of the table in "Maximum Ratings" (p. 51).
When cooling measures are used, the limit values for the operating frequency, operating
voltage and operating time increase.

Peak and average output current of the electronics (p. 12) used:
The electronics must be selected so that it fulfills the following requirements:
−
The electronics can provide the required current. See "Calculating the Power
Requirement for Sinusoidal Operation" (p. 39).
−
The output current of the electronics does not exceed the maximum power
consumption of the piezo actuator. See "Maximum Ratings" (p. 51).
−
The control signal of the electronics does not have steep edges. See "General Notes
on Start-Up and Operation" (p. 31).