Delphin ProfiMessage, Hardware Manual

Page: 258 / 322

Profi Message
For measurements using acceleration sensors, a vibration velocity signal (unit
m/s2) is converted into a vibration speed signal (unit mm/s). Refer to the "Applic-
ations using AMDT" manual.
Restrictions
The digital integrator is also subject to these restrictions:
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Board V2.00 to V2.12
For 1 ... 4 analogue inputs: Integrator available
For 5 ... 8 analogue inputs: Integrator not available
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Board V2.13 and higher
For 1 ... 8 analogue inputs: Integrator available
When digital integration is enabled, measurement-range checking or
wire-break monitoring will not take place.
9.2.4 FFT analysis/frequency spectrum
Vibration signal recordings are initially saved to a buffer within the I/O module.
Options are available to then perform an FFT analysis or to compute a frequency
spectrum. Each analogue input channel is provided with an additional “FFT/spec-
trum” channel. This delivers a block of measurement data (e.g. 800 amplitude val-
ues concerning frequency).
Properties
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An “FFT/spectrum” channel can be created separately (for each analogue
input).
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FFT algorithms for 1024, 2048, or 4096 points or with 400, 800, or 1600
lines.
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Frequency range, number of lines and frequency resolution can be set.
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Standard window functions 'Hanning', 'Flat Top', etc. can be chosen.
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Data compression can be used for transmission and storage.
Scaling
“FFT/spectrum” channels can be individually scaled. Scaling takes place in the
required unit (e.g. ± 100 µm for distance/clearance sensors or ±50 g for accel-
eration sensors).
Application
Analysis of characteristic frequencies and their amplitudes for a measured vibra-
tion signal.
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Delphin Technology AG
Dezember 2015
Profi Message Manual