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3408/3410/3412 Series Industrial PC System Manual
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the female pem located on the side of the power connector opening. When installing
the power cable to the unit, use the securing screws on each side of the plug.
Warning
Be sure to completely loosen the two securing screws on the plug when
disconnecting the power cord from the unit.
Installing the System into a Panel
The system’s rugged design allows it to be installed in most industrial environments. The
system is generally placed in a NEMA 4/4X/12 enclosure to protect against contaminants
such as dust, moisture, etc. Metal enclosures also help minimize the effects of electro-
magnetic radiation that nearby equipment can generate.
System Power
Using isolation transformers on the incoming AC power line to the system is always a
good practice. An isolation transformer is especially desirable in cases in which heavy
equipment is likely to introduce noise onto the AC line. The isolation transformer can
also serve as a step-down transformer to reduce the incoming line voltage to a desired
level. The transformer should have a sufficient power rating (units of volt-amperes) to
supply the load adequately.
Proper grounding is essential to all safe electrical installations. Refer to the relevant fed-
eral, state/provincial, and local electric codes which provide data such as the size and
types of conductors, color codes and connections necessary for safe grounding of electri-
cal components. The code specifies that a grounding path must be permanent (no solder),
continuous, and able to safely conduct the ground-fault current in the system with mini-
mal impedance (minimum wire required is 18 AWG, 1 mm).
Observe the following practices:
•
Separate ground wires (P.E. or Protective Earth) from power wires at the point of
entry to the enclosure. To minimize the ground wire length within the enclosure, lo-
cate the ground reference point near the point of entry for the plant power supply.
•
All electrical racks or chassis and machine elements should be Earth Grounded in in-
stallations where high levels of electrical noise can be expected. The rack/chassis
should be grounded with a ground rod or attached to a nearby Earth structure such as
a steel support beam. Connect each different apparatus to a single Earth Ground
point in a “star” configuration with low impedance cable. Scrape away paint and
other nonconductive material from the area where a chassis makes contact with the
enclosure. In addition to the ground connection made through the mounting bolt or
stud, use a one-inch metal braid or size #8 AWG wire to connect between each chas-
sis and the enclosure at the mounting bolt or stud.