Multichannel Systems ME-System Manual - Manual (Page 18)

ME-System Manual
18
2.7 Data Acquisition
Recording from up to 256 channels is easy with the MC_Card hardware or with USB based data
acquisition device and the MC_Rack software.
2.7.1 MC_Card Hardware
Important: You need to have installed the latest MC_Card driver to operate the MC_Card,
which is usually preinstalled on the data acquisition computer. The installation may be
invalid if the MC_Card does not respond. Please contact Multi Channel Systems MCS GmbH
if you need the MC_Card Driver and a description of the installation.
The MC_Card is an A/D board that converts analog signals in real time into digital data streams
at sampling rates of up to 50 kHz for all channels. You will not miss even the fastest signals.
You configure the input voltage range from +/- 400 mV to +/- 4V and the sampling rate
with the software controls in the MC_Rack program. Please refer to the MC_Rack Help or
Manual for more information.
Please see the MC_Card data sheet for additional information on the pin layouts and the
technical specifications.
2.7.2 USB based Data Acquisition
The USB-ME64 / 128 / 256-System are stand-alone solutions for acquiring data from up to
256 channels. They can replace the internal computer hardware MC_Card. The analog input
signals are acquired and digitized by the USB-ME-System and the digital electrode signals
are transmitted to the connected computer via universal serial bus (High Speed USB 2.0).
Thus, it is possible to use any computer for data processing. Please refer to the USB-ME64- /
128- / 256-System manuals
respectively.
2.7.3 DC Offset Correction
An offset correction is generally not necessary, because the intrinsic DC offsets of the
MCS amplifier outputs and the MC_Card are very low in comparison to the signals of interest.
The maximum DC offset of the MC_Card is +/– 2 mV. For example, with a total gain of 1000,
this results in a maximum offset of only 2 μV (+/– 2 mV divided by 1000) for the input signals.
You can use the MC_Rack offset correction feature to remove even this low offset and reset
all channels to zero. Please refer to the MC_Rack Help or Manual for more information.
Note: If you observe a large offset on any channel(s), you should contact your local retailer for
troubleshooting. The offset correction is not intended for removing large offsets, because the
offset correction will decrease the input voltage range.