Platinum Z5 CD, Руководство пользователя

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WARNING: Disconnect primary power prior to servicing.
Installation & Initial Turn-On
2.5.6.3 Grounding
The importance of a good grounding system and lightning protection can hardly be
overemphasized for reasons of personnel safety, protection of the equipment, and
equipment performance. The following is only a brief overview.
Lightning and transient energy via the power line or tower connections can impose
serious threats to your personal safety as well as damage the equipment. For these
reasons you should have a good protective earthing system to divert these forms of
energy to earth ground. Proper grounding of the equipment also guards against
electrical shock hazards that would exist if the equipment failed in a way which put
a hazardous voltage on the chassis.
A good grounding system should include substantial grounding at the tower base
using copper ground rods and/or a buried copper ground screen, with copper strap
used to connect the tower base to earth ground. A low impedance will help carry
lightning current directly into the ground instead of into your building. Additionally,
coax shield(s) should be electrically connected to and exit the tower as near to the
bottom as practical to minimize the lightning voltage potential carried by the coax
into your building.
For coaxes, a single point of entry into the building is best, with all connected to a
common grounding plate (or bulkhead panel) having a low impedance connection
to the building perimeter ground. Wide copper straps should be used for making the
connection from the common grounding plate to earth ground.
A common grounding plate is also the best location for coaxial surge protectors for
sensitive equipment such as an STL receiver. Ideally, this plate should also be the
entry point for all signal lines, and serve as a single point ground for AC power
surge protection.
A good ground system should include perimeter grounding of the transmitter
building using copper ground rods and copper strap. There should also be a copper
strap running from tower ground to the building perimeter ground.
Good grounding and shielding will help keep stray RF current to a minimum. RF
interference usually shows up in one of several ways, intermittent problems with
digital or remote control circuits, audio feedback or high pitched noise. Even a
small amount of non-shielded wire makes a very efficient antenna for RF and
transient energy. If RF is allowed into the audio equipment, it can be rectified and
may show up as noise or feedback. Wire and cable shields should normally be
connected at both ends to the equipment chassis.