User guide

10 WZ14:4:2 U
SER
G
UIDE
NO USER SERVICEABLE PARTS INSIDE.
SUPPLY VOLTAGE RANGE:
100 - 240V
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.
47-63Hz ~ 30W MAX
WARNING - THIS APPARATUS MUST BE EARTHED.
REFER TO USER GUI DE BEFORE CONNECTING SUPPLY
TO REDUCE THE RI SK OF FIRE OR ELECTRIC SHOCK
DO NOT EXPOSE THIS APPARATUS TO RAIN OR MOISTURE.
AVIS: RISQUE DE CHOC ELECTRIQUE - NE PAS OUVRIR.
REPLACE FUSE WITH SAME TYPE AND RATING
WARNI NG: FOR CONTINUED PROTECTION AGAINST RISK OF FIRE
ATTENTI ON: REMPLACER LE FUSIBLE AVEC UN DES MEMES CARACTERISTIQUES.
100 - 240V~ T500mA 250V 20mm
CAUTION
FUSE
OF F
AC MAINS IN ~
ON
~
C
ONNECTING
M
AINS
P
OWER
Refer to the SAFETY WARNING on page 5 of this
Guide. Check that the correct mains lead with moulded
plug has been supplied with your console. Read and
understand the warnings and instructions printed on the
rear panel and reproduced here. The power supply
accommodates mains voltages within the range 100-
240V without changing any fuses or settings.
It is standard practice to turn connected power
amplifiers down or off before switching the console on or
off. Ensure that the IEC mains plug is pressed fully into
the rear panel socket before switching on.
E
ARTHING
The connection to earth (ground) in an audio system is important for two reasons:
1. SAFETY - To protect the operator from high voltage shock associated with the AC mains
supply feeding the system, and
2. AUDIO PERFORMANCE QUALITY - To minimise the effect of earth (ground) loops which
result in audible hum and buzz, and to shield the audio signals from interference.
For safety it is important that all equipment earths are connected to mains earth so that
exposed metal parts are prevented from carrying high voltage which can injure or even kill
the operator. It is recommended that the sound engineer check the continuity of the safety
earth from all points in the system including microphone bodies, guitar strings, multicore
cases, equipment panels ...
The same earth is also used to shield audio cables from external interference such as the
hum fields associated with power transformers, lighting dimmer buzz, and computer
radiation. Problems arise when the signal sees more than one path to mains earth. An
‘earth loop’ (ground loop) results causing current to flow between the different earth paths.
This condition is usually detected as a mains frequency audible hum or buzz.
To ensure safe and trouble-free operation we recommend the following:
x
Do not remove the earth connection from the console mains plug. The console
chassis is connected to mains earth through the power cable to ensure your safety. Audio
0V is connected to the console chassis internally. If problems are encountered with earth
loops operate the audio ‘ground lift’ switches on connected equipment accordingly, or
disconnect the cable screens at one end, usually at the destination. It is useful to carry
ground lift cable adapters such as short XLR male to female leads with pin 1
disconnected.
x
Avoid running audio cables next to mains, computer or lighting cables, or near
thyristor dimmer and power supply units. If unavoidable, cross these at right angles.
x
Use low impedance sources such as microphones rated at 200 ohms or less to reduce
susceptibility to interference. The console outputs are designed to operate at very low
impedance to minimise interference problems.
x
Use balanced connections where possible as these provide further immunity by
cancelling out interference that may be picked up on long cable runs. To connect an
unbalanced source to a balanced console input, link the cold input (XLR pin 3 or jack ring)
to 0V earth (XLR pin 1 or jack sleeve) at the console. To connect a balanced console
output to an unbalanced destination, link the cold output to 0V earth at the console.
x
Use professional quality cables and connectors and check for correct wiring and
reliable solder joints.
x
If you are not sure ... Have your system checked by a competent engineer, or contact
your local Allen & Heath agent for advice.