Determining The Operating Parameters; Overview Of Limiting Factors - PI P-88 Series User Manual

6 Starting and Operating
NOTICE
Destruction of the piezo actuator due to rapid cooling or heating!
Cooling down or heating up too quickly leads to a thermomechanical load that can destroy the
piezo actuator.
 Allow the piezo actuator to cool down or warm up slowly.
NOTICE
Uncontrolled oscillation!
Oscillation can cause irreparable damage to the P-88x/P-08x. Oscillation is indicated by a
humming noise and can be caused by the following:
A change in the load and/or dynamics requires the servo control parameters to be

adjusted.
The P-88x/P-08x is operated near to its resonant frequency.

If you notice oscillation:
 In closed-loop operation, switch off the servo mode immediately.
 In open-loop operation, stop the P-88x/P-08x immediately.
INFORMATION
The positive direction of motion (p. 11) corresponds to the expansion direction of the piezo
actuator when a positive voltage is applied.
6.2

Determining the Operating Parameters

INFORMATION
For determination of the the operating parameters, it is assumed that the piezo actuator is
clamped on one side.
 If you require operating parameters for unclamped operation of the piezo actuator,
contact our customer service department (p. 45).
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 frequency
according to the data table (p. 47) applies to unclamped operation without load. In an
arrangement with unilateral clamping, the value must be halved.
For loaded piezo actuators that are clamped on one side, see "Calculating the Maximum
Operating Frequency of the Loaded Piezo Actuator" (p. 37).
P-88x/P-08x Piezo Actuator PZ259E Version: 1.1.0 35