Measurement Computing PCM-DAS16x/16 User Manual
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products to add electrical isolation, or give our technical support group a call to dis-
cuss other options).
NOTE
Relying on the earth prong of a 120VAC for signal ground connec-
tions is not advised.. Different ground plugs may have large and
potentially even dangerous voltage differentials. Remember that the
ground pins on 120VAC outlets on different sides of the room may
only be connected in the basement. This leaves the possibility that
the “ground” pins may have a significant voltage differential (espe-
cially if the two 120 VAC outlets happen to be on different phases!)
6.1.11 PCM-DAS16x/16 and Signal Source already have Isolated Grounds
Some signal sources will already be electrically isolated from the PCM-DAS16x/16.
The diagram below shows a typical isolated ground system. These signal sources are
often battery powered, or are fairly expensive pieces of equipment (since isolation is
not an inexpensive proposition), isolated ground systems provide excellent perform-
ance, but require some extra effort during connections to assure optimum perform-
ance is obtained. Please refer to the following sections for further details.
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