User manual

PAGE 4
User Manual PS 285 / Issue 2011 © ASL Intercom BV
WARNING
This appliance must be earthed
4.0 MECHANICAL INSTALLATION
A vertical rack space of 1U (1.75” / 44,5 mm) is
required for the PS 285. It is not necessary to
provide rear support by extra bracing or shelving.
Adequate ventilation must be provided by allowing
sufficient space around the sides and rear of the unit
to ensure free circulation of air.
Forced cooling is not required. The power supply
regulator is mounted on the bottom of the PS 285.
After a period of time it will feel hot to the touch on
top and bottom. This is normal and should be no
cause for alarm.
5.0 GENERAL DESCRIPTION PS 285
The PS 285 is a dual channel booster power supply
which is used to power those user stations in an
intercom system which can‟t be powered by the
master power supply (a PS 279 master station or a
PS 289 separate power supply), due to the line
power capacity of the PS 279 / PS 289.
(see section 14 “System Configuration”).
The PS 285 is also used in case the intercom lines
(party lines) are very long as a result of which - at a
certain distance from the master power supply - the
available line power voltage is in danger to drop
below the required minimum level.
.
The PS 285 is fully protected and can drive at least
20 beltpacks or 10 speaker stations operating at full
power.
Remotely activating the PSU of the PS 285:
As soon as line power, provided by the master power
supply in an intercom system, is sensed at an input
connector of the PS 285, its power supply module is
activated for the referring channel. The yellow “On”
LED of that channel lights up.
If no line power is sensed, the referring channel of
the PS 285 is in “Standby Mode” and its green
“Standby” LED is illuminated (see also “Powering up”
in section 6).
6.0 MAINS POWER
The PS 285 may be connected to a mains power
outlet of 100 - 240 V AC (50 - 60 Hz), 100 watts.
The outlet should have a clean earth. Avoid using
mains power outlets which also power dimmer
controlled lighting equipment. Fuse type all voltages:
T 1250
The wires in the mains lead are color coded:
Green/yellow: safety ground
Blue: neutral
Brown: live
In case the colors of the wires in the mains lead do
not correspond with the colored markings of the
terminals in your plug, proceed as follows:
o The wire that is colored green-and-yellow
must be connected to the terminal in the
plug, which is marked with the letter “E”, or
by the ground symbol, or is colored green.
o The wire that is colored blue must be
connected to the terminal that is marked with
the letter “N” or colored black.
o The wire that is colored brown must be
connected to the terminal marked with the
letter “L” or colored red.
The green-and-yellow wire of the mains cord must
always be connected to the electrical installation
safety earth or ground. This is essential for personal
safety as well as for proper operation of the PS 285
and connected user stations.
This wire internally connected to all exposed metal
surfaces. Any rack framework into which this unit
might be mounted shall be connected to the same
grounding circuit.
The PS 285 employs professionally designed audio
input and output circuits which do not require the
disconnection of any safety earth to avoid hum loops.
Powering up procedure:
Make sure that the red power switch on the
left side of the front panel is OFF.
Connect the power cord to the rear of the
station.
Plug the other end of the power cord into a
properly grounded mains outlet.
Turn on the power with the red button. The
red overload LED will light up for about 3
seconds and then extinguishes. The green
LEDs of channel A and B are now lit,
indicating that the PS 285 is in standby
mode.
As soon as a powered party line (coming
from the master power supply in an ASL
intercom system) is connected to an
intercom line input of the PS 285, the yellow
„On‟ LED of the referring channel lights up,
indicating that line power is supplied to the
intercom line output connector of that
channel.