Harris DiamondCD Series, Техническое руководство

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B-2 888-2463-001 3/6/08
WARNING: Disconnect primary power prior to servicing.
Diamond Series™
Appendix B Surge, Lightning and
In cases where driven ground rods are used for building ground, the primary and
secondary neutrals must be separated by a spark gap. If two separate ground rods are
used, the rods must be at least 20 feet apart. All connections between lightning
arrestors, line connections, and ground must be made as short and straight as possible,
with no sharp bends.
B.2 System Grounding
Signals employed in transmitter control systems are on the order of a few microseconds
in duration, which translates to frequencies in the megahertz region. They are therefore
radio-frequency signals, and may be at levels less than 500 microvolts, making them
susceptible to noise appearing on ground wires or adjacent wiring. Thus, all ground
wiring must be low in impedance as well as low in resistance, without splices, and as
direct as possible. Four basic grounds are required:
a.
AC ground
b. DC ground
c. Earth ground
d.
RF ground
B.2.1 Ground Wires
Ground wires should be at least as large as specified by the local electrical code. These
leads must be low impedance direct runs, as short as possible without splices. In
addition, ground conductors should be insulated to prevent intermittent or unwanted
grounding points.
Connection to the earth ground connection must be made with copper clamps which
have been chemically treated to resist corrosion. Care must be taken to prevent
inadvertent grounding of system cabinets by any means other than the ground wire.
Cabinets must be mounted on a support insulated from ground.