Field Wiring Considerations - Advantech PCL-818 Series User Manual

3.4 Field Wiring Considerations

When you use the PCL-818HD/HG/L to acquire data from outside, noises
in the environment might significantly affect the accuracy of your mea-
surements if due cautions are not taken. The following measures will be
helpful to reduce possible interference running signal wires between sig-
nal sources and the PCL-818HD/HG/L.
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 interference.
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 inter-
ference, 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 con-
nected 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 distance
between them. Alternatively, you can place the signal cable at a right
angle to the power line to minimize the undesirable effect.
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
that you use the PCL-10137 shielded cable.
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