3. Installation
Mains Lead Wiring
WARNING
Your amplifier must be earthed at all times!
When you first receive your amplifier it may not have
a mains plug attached. You must ensure that an
appropriate plug is used and corresponds with the
amplifier’s current (ampere) requirements and meets
the approval of your local energy authority.
Please refer termination of this lead to qualified
personnel. Australian Monitor takes no
responsibility for any damage or harm resulting
from improper termination of this lead!
The wires in the mains lead are coloured in accordance
with the following code:
GREEN AND YELLOW = EARTH
Connect to the terminal marked with the letter E, with
the EARTH SYMBOL or coloured GREEN.
BLUE = NEUTRAL
Connect to the terminal marked with the letter N (or
coloured WHITE in USA and Canada, or coloured
BLACK in the United Kingdom).
BROWN = ACTIVE (LIVE)
Connect to the terminal marked with the letter A or L
(or coloured BLACK in USA and Canada or coloured
RED in the United Kingdom).
Power Requirements
Mains Voltage
Circuit Breaker Rating
100 to 120 volts
20 Amps
220 to 240 volts
10 Amps
Power Consumption at idle
= 250 Watts
Consumption at rated 4 ohm power
= 2300 Watts
Ensure that your mains voltage is the same as the rear
panel mains voltage marker (+/- 10%).
Mounting
Your amplifier is designed for standard 19" rack
mounting and occupies 3 EIA rack units (5.25"). The
mounting centres are:
Vertical:
2.25" (57.15mm)
Horizontal: 18.15" (461.1mm) to 18.62" (473.0mm).
The slots in the mounting flange will accept bolt
diameters up to 1/4" (6.35mm).
We recommend that you provide additional support for
the amplifier, especially if road use is planned, as the
weight can bend some racks otherwise. This support
can be provided by secure shelving, support rails or a
rear rack mounting strip to match up with the rear rack
mount points provided on your amplifier.
Cooling
Each pair of channels in your
AM1200
amplifier is
cooled by an axial fan which draws cool air from the
front of the unit and expels the heated air via the rear
of the unit. These units offer two speed fans which run
at half speed, switching to full speed when the internal
heatsink temperature exceeds 60
0
C (128
0
F).
An unrestricted airflow into and out from the unit must
be provided. Any restriction of the air flow will cause
heat to build up within the unit and possibly force the
unit into its thermal shutdown mode.
If the units are to be operated in an environment
where the airflow is restricted such as sealed racks or
even when running 2 ohm loads, the cooling should
be supplemented by extra cooling fans to evacuate
the heated air and aid the flow of cool air through the
unit.
Input Wiring
IMPORTANT! Do not directly connect pin 1 on the
amplifier’s input or strapping XLR, to the amplifier’s
chassis, speaker ground or power ground!
NOTE: Input signal ground is not to be used as
a safety ground (earth).
The input to your amplifier is a balanced 3-pin system
and requires all three pins to be connected. Only high
quality twin-core shielded cable should be used.
When wiring for a balanced source the connector
going to the input of your amplifier should be wired as
follows:
Pin 2 = HOT (In Phase - non inverting).
Pin 3 = COLD (Reverse Phase - inverting).
Pin 1 = GROUND / SHIELD.
When wiring from an unbalanced source you must
ensure that pin 3 is connected to pin 1 (input ground),
either by linking the pins in the input connector or by
the source equipment's output wiring.
When wiring for an unbalanced source:
Pin 2 = HOT (in phase with the amplifier’s output),
Pin 3 = GROUND/SHIELD (joins to pin 1).
Pin 1 = GROUND/SHIELD
Installation 11