Advantech PCI-1241, User Manual

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PCI-1241/1242 User Manual 38
3.6.3 Field Wiring Considerations
When you use the PCI-1241/42 motor control card to connect with motor
drivers, noises in the environment might significantly affect the accuracy
of your control if due cautions are not taken. The following measures will
be helpful to reduce possible interference running signal wires between
signal sources and the PCI-1241/42.
• The signal cables must be kept away from strong electromagnetic
sources such as power lines, large electric motors, circuit breakers or
welding machines, since they may cause strong electromagnetic inter-
ference. Keep the analog signal cables away from any video monitor,
since it can significantly affect a data acquisition system.
• If the cable travels through an area with significant electromagnetic
interference, you should adopt 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.
• Avoid running the signal cables through any conduit that might have
power lines in it.
• If you have to place your signal cable parallel to a power line that has a
high voltage or high current running through it, try to keep a safe dis-
tance between them. Or you should place the signal cable at a right
angle to the power line to minimize undesirable effects.
• The signals transmitted on the cable will be directly affected by the
quality of the cable. In order to ensure better signal quality, we recom-
mend that you use the PCL-10168 shielded cable.