System Power; Heat - Xycom 9450 Manual

9450 Industrial PC/AT Computer System
The displays may be affected by Geomagnetic fields. Some typical effects of magnetic
fields are purity (blotchy colors), distorted screens, etc. In some cases, purity problems
may be correctable by powering off the unit for 30 minutes and reapplying power. In
other cases a degaussing wand may be needed. Contact Xycom's Application Engi-
neering department for further questions.

System Power

It is always a good idea to use isolation transformers on the incoming AC power line to
the 9450. 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 National
Electric Code (NEC), article 250, which provides data such as the size and types of con-
ductors, color codes and connections necessary for safe grounding of electrical compo-
nents. The code specifies that a grounding path must be permanent (no solder), continu-
ous, and able to safely conduct the ground-fault current in the system with minimal im-
pedance. The following practices should be observed:
•
Separate ground wires from power wires at the point of entry to the enclosure. To
minimize the ground wire length within the enclosure, locate the ground reference
point near the point of entry for the plant power supply.
•
All electrical racks or chassis and machine elements should be grounded to a central
ground bus, normally located near the point of entry for the plant power supply of
the enclosure. Paint and other nonconductive material should be scraped away from
the area where a chassis makes contact with the enclosure. In addition to the ground
connection made through the mounting bolt or stud, a one-inch metal braid or size #8
AWG wire can be used to connect between each chassis and the enclosure at the
mounting bolt or stud.
•
The enclosure should be properly grounded to the ground bus. Make sure a good
electrical connection is made at the point of contact with the enclosure.
•
For continued safety, power ground should be connected to earth ground.

Heat

The 9450 is designed to withstand temperatures from 0º to 50º C. The system is convec-
tion cooled, in which a vertical column of air is drawn upward over the surface of the
components. To keep the temperature in range, the cooling air at the base of the system
must not exceed 50º C. Proper spacing must also be allocated between internal compo-
nents installed in the enclosure.
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Note