Auditronics ALM-12d, Техническое руководство, Страница: 12 / 101

I N S T A L L A T I O N a n d P O W E R
page 1 – 4
ALM-12d / Oct 2001
(B) THE POWER COMPANY EARTH CONDUCTOR that enters the build-
ing at the power line breaker box; this conductor should be (and is often by code)
tied to the above-mentioned earth ground at one point. This point is the SYSTEM
EARTH GROUND.
TIE THE CONSOLE GROUND LUG TO THE SYSTEM EARTH
GROUND. TIE EVERY PIECE OF EQUIPMENT IN THE ENTIRE
AUDIO SYSTEM TO THE CONSOLE GROUND LUG. If the system
earth ground point is inaccessible, tie the console ground lug to the power
company earth conductor at the main breaker box (see drawing "Typical
Grounding Scheme" on previous page).
Each piece of equipment should be connected by its own ground wire
(usually the round third pin on the AC cord). This means that every AC
outlet must have a separate conductor run to the console ground lug; the
outlets cannot be daisy-chained as is normally encountered in commercial
and residential AC systems. Any equipment not supplied with 3-wire AC
cables must have individual ground wires (16 gauge or larger) connected
to their chassis grounds and then run to the console ground lug terminal
strip.
Further Grounding Details
Check all equipment to be absolutely certain that each unit is power
transformer isolated from the AC mains to prevent safety hazards.
It is assumed that in each piece of audio equipment the audio ground
and the chassis are tied together at some point. Any piece of equipment
lacking a grounded chassis is likely to be prone to interference problems.
Locate all unbalanced audio equipment in the same rack if possible, to
minimize chassis ground potential differences. It may also be helpful to
insulate each piece of unbalanced equipment from its mounting rails in the
rack by means of nylon 10-32 screws and insulating washers between rails
and faceplates.
Once the system is properly grounded, proceed with the console
power supply installation and connection (next section).
Power Supplies
The ALM-12d console is powered by a Wheatstone Model PSC-D340
rackmount power supply. This heavy duty unit occupies three 19” wide
rack spaces (total height 5-1/4”). Convection cooled, it requires ample
ventilation space above and below it. The PSC-D340 generates a lot of
heat in the course of normal operation — do not mount heat sensitive
devices in the same rack cabinet.
Note the power supply should be mounted in an equipment rack within
fifteen feet of the console (but no closer than 3 feet). Avoid locating any
high gain equipment (such as phono preamps, tape recorders, etc.) too near
the rackmount supplies, to avoid magnetic interference into that equip-
ment.
If failsafe redundant sup-
plies have been ordered,
you will be installing two
units and an additional
rackmount panel.