Advantech PCI-1727U, Руководство пользователя

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PCI-1727U User Manual 26
Field Wiring Considerations
When the PCI-1727U acquires data from outside, noise in the environ-
ment might affect the accuracy of your measurements if preventative
measures are not taken. The following is helpful to reduce running signal
wire interference between signal sources and the PCI-1727U.
The signal cables must be kept away from strong electromagnetic sources
such as power lines, large electric motors, circuit breakers or welding
machines, as they may cause strong electromagnetic interference. Keep
the analog signal cables away from any video monitor, as it can signifi-
cantly affect a data acquisition system.
Avoid running cables through any conduit that may contain power lines.
If it is necessary to place a signal cable parallel to a power line with a
high voltage or current, try to keep a safe distance between them. Place
the signal cable at a right angle to the power line to minimize the effect.
If the cable travels through an area with significant electromagnetic inter-
ference, substitute individually shielded, twisted-pair wires as the analog
input cable. This type of cable has its signal wires twisted together and
shielded with a metal mesh. The metal mesh should only be connected to
one point at the signal source ground.
The signals transmitted on the cable will be directly affected by the qual-
ity of the cable. In order to ensure better signal quality, we recommend
the PCL-10137 shielded cable.