2-2
2 Introduction
Scanning head
details
Two versions of the scanning heads are available: Standard and Xtra.
In the Standard scanning head, a helium-neon laser with a wavelength of
632.8 nm and a maximum output power of 1 mW is used.
In the Xtra scanning head, an infrared laser with a wavelength of 1 550 nm
and a maximum output power of 10 mW is used. The Xtra version has a
higher sensitivity and higher velocity ranges. In order to make the laser beam
visible, this version uses a green pilot laser.
Front-end
details
In the front-end, the interferometer signals of the vibrometers are
demodulated using velocity decoders and transmitted to the PC via an analog
interface. Synchronously to the vibrometer data, reference channels are
acquired and generator signals are emitted.
The front-end recognizes automatically which scanning head versions are
connected (Standard or Xtra). The scaling of the vibrometer ranges is adapted
automatically. However, make sure to connect only scanning heads that have
the same wavelengths!
Junction box
details
The PSV-E-500 junction box is the connection point between the scanning
heads and the front-end. In addition to that, the video signal from the TOP
scanning head is transmitted to the PC via the junction box.
The measurement data is acquired and saved in the PC. The PSV software
controls the entire measurement system and offers user-friendly functions to
evaluate the measurement data.
2.2
Signal Flow between the System Components
2.2.1
Principle
In the front-end, the high-frequency Doppler signal coming from the scanning
head is fed in the decoder. Here, the velocity information is extracted from the
signal. Analog reference signals are connected to the front-end and generator
signals are emitted. The measurement data is transmitted to the PC as analog
signals. The signal flow in the system is shown in the following figure.
Figure 2.2:
Schematic diagram of the signal flow in the PSV-500-3D
Generator
D/A
Vibrometer,
Reference
A/D
PC
Reference signals
Generator signals
Control signal
Vibrometer signals
Camera signal
Generator connections
Reference connections
3 d
s
ecoder
Front-end
Control signals
Doppler
signals
Junction box
Camera signal
Control signals
Doppler
signals
Scanning heads
Summary of Contents for PSV-500-3D
Page 19: ...2 4 2 Introduction ...
Page 55: ...4 10 4 Measuring ...
Page 63: ...6 6 6 Troubleshooting ...
Page 97: ...A 12 A Optional Accessories ...
Page 101: ...C 2 C Declaration of Conformity ...