Title: Folie 1
1Multichannel Data Acquisition and Analysis
2Overview
The VIPER multi channel data acquisition system
provides a perfect way to measure data on a large
number of input channels at a very high speed.
One master PC can control up to 20 VIPER-48
units via Ethernet. The complete system has 960
channels with per channel sampling rates of up to
250 kHz. An intelligent clock and trigger
distribution allows the synchronisation of all
units. Modern Floating Point DSPs are used for
online processing and control of high quality
signal conditioning modules. Direct connection of
different sensors makes VIPER usable in a wide
range of data acquisition applications.
3System Architecture
- PC-unit
- Industry passive backplane, with all-in-one CPU
board - RAM memory 1 GByte
- Processor Pentium 4 2.8 GHz
- Operating system Windows XP Professional
- 1000 MBit Ethernet connection
- 240 GByte EIDE hard disk
- External connectors
- VGA monitor
- PS/2 keyboard
- PS/2 mouse
- 1000 MBit Ethernet LAN
- 4 x USB
4System Architecture
- DSP unit
- 6 PCI DSP boards with TMS320C6701 DSP (1 GFLOP )
- each board 16 MByte SDRAM (DSP program code
memory and data buffer memory) - ADC unit
- Sigma-Delta 16 Bit ADC with 8 times over
sampling. Effective sample frequency up to 250
kHz with 100 kHz bandwidth. - first anti-aliasing filter realised as analog
anti-aliasing filter in analog signal
conditioning unit. - second anti-aliasing filter realised as digital
hardware FIR filter inside the ADC chip - down sampling and additional digital FIR-filter
realised in DSP software - external triggering and sampling is possible
(necessary for phase locked trigger and sample
technique)
5System Architecture
- Networking
- up to 20 VIPER-48 Units can be connected via
Ethernet and synchronised
6Technical Specifications
- Channels
- max 48 channels per Viper System
- unlimited number of total channels
- all channels running synchronous via SYNC-Bus
- 16 Bit resolution, up to 250 kHz sampling rate
- input voltage /- 14.142 V 10 V RMS
- gain 0.5 .. 500.000 in steps of 1-2-5-10
- coupling AC/DC/GND/CAL
- mode single ended or differential
- SNR typically 80dB _at_ Gain 1 70dB _at_ Gain 1000
- connection via BNC, Lemo and Sub-D connector
7Technical Specifications
- Acquisition time
- limited only by hard disk capacity (currently 2.5
hours for 48 channels at 250 kHz each) - Trigger/clock
- analogue level trigger
- digital start measurement trigger
- external 1P clocking for phase locked measurement
- Specials
- overload detection and statistics
- analogue level LEDs
- direct connection for BK microphones and ICP
sensors - autoranging of all activated channels
- insert calibration for microphones
- optional real time 1/n octave spectral
calculation (digital filter banks in the time
domain)
8ASC-8 Analog Signal Conditioning Unit
9ASC-8 Analog Signal Conditioning Unit
- Unit type
- Europa Card format (100mm x 227mm, 21TE )closed
metal case - Connection to back plane
- 64 pole standard connector DIN 41612
- Number of channels per unit
- 8 channels
- Board name
- Eight Channel Analogue Signal Conditioning
(ASC-8) - Input connectors
- isolated BNC differential or single-ended (remote
selectable) - Lemo differential or single-ended (remote
selectable) - 25 pin-Sub-D connector
10ASC-8 Analog Signal Conditioning Unit
- Input
- /- 14.142 V 10 Vrms with impedance 1MOhm
- Input Coupling
- single ended / differential (remote selectable)
- AC / DC (remote selectable)
- GND (remote selectable)
- Calibration (remote selectable)
- Ins Calibration (remote selectable)
- Gain
- pre gain 0.5 / 1 / 5 / 10 (remote selectable)
- mid gain 1 / 10 / 100 / 1000 (remote
selectable) - post gain 1 / 2 / 5 / 10 / 20 / 50 (remote
selectable)
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12ASC-8 Analog Signal Conditioning Unit
- Filters
- analog Anti-Aliasing filter fixed at 103kHz, 6
pole Butterworth - Overload signal
- Red LED per channel controlled by DSP via digital
I/O-interface - LED stays active until next measurement(memory
function for very short overloads) - Green/Red LED per channel controlled by
analog-amplifier - Output signal
- /- 2V to ADC
- Sensor signal after amplification and filtering
(/- 14.142V) buffered available on BNC (signal
monitoring)
13ASC-8 Analog Signal Conditioning Unit
- Sensor power supply
- 5 / 10 / 12 / 15 VDC (selectable via jumper to
Lemo pin X)display selected voltage with LED's
on front panel - 120 VDC and 200VDC (polarisation voltage for BK
microphones, enable via jumper to Lemo pin
Y)display enable status with LED on front panel - Current source 4mAdisplay enable status with LED
on front panel
14Software
- Programming Interface as VIPER.dll, easy to use
with Visual C/C and Visual Basic - Viper-View Standard Windows Software for
configuring measurements, with real time display
and real time FFT - Famos data format (binary with ASCII header)
- Option real time octave analysis and RMS
calculation, running on DSPs on every VIPER Unit