ZETRON 4000 Series, Руководство по установке

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System Grounding
System Grounding
Proper earth grounding is an important electrical consideration. The earth ground protects
the system and personnel from lightning strikes, provides a path for any electrostatic
discharge (ESD), and provides a solid reference for the system. Improper grounding of the
system could cause susceptibility to ESD, induced noise from input power wiring, and
reduced effectiveness of lightning protection devices. Induced noise could cause false
signal indications or a variety of system errors.
A “star” grounding system (a single point ground to which satellite grounds are
connected) is the best grounding system. The central point must be firmly attached to a
low-impedance earth ground point, such as a ground rod.
If protective punch-down blocks are used, a large diameter (6 - gauge) copper conductor (or
an equivalent braided strap/bus bar) must be connected between each block’s ground lug
and the earth ground or central ground point. With the protected punch-down blocks, it is
best to wire directly to earth ground if possible. Each piece of equipment should have its
chassis grounded to the central point with a separate ground wire. The gauge of the wire
depends on the length of the run; 12 gauge is adequate if the length is less than 15 feet.
The length of the runs should be minimized. Securely connect a grounding wire to the case
of each unit, making sure metal connection is made (no paint or oxidation layer). Most
Zetron equipment provides a grounding stud. If the console includes a computer, connect
an individual grounding wire to the computer chassis. Figure 11 shows a central “star”
grounding system.
All earth grounds in the system should be isolated from signal lines. It is easy to couple
ESD or lightning noise spikes if these lines run parallel for any distance. The AC power
wires (and DC power to a lesser degree) should also be routed separately. AC lines can
have large switching current noise spikes that could couple into signal lines.
DANGER! Improper system grounding can cause electric shock to
personnel, damage to equipment, and system malfunctions.