PAGE 5
User Manual PS 279 / August 2016 © ASL Intercom BV
4.0
MECHANICAL INSTALLATION
A vertical rack space of 1U (1.75” / 44,5 mm) is
required for the PS 279. 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 is mounted on the bottom of the
PS 279. 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
FRONT PANEL CONTROLS AND CONNECTOR
1
OVERLOAD LED
This red LED illuminates if the circuit breaker
shuts off line power due to overload. A cause for
overload can be too many user stations
connected or a short circuit in the interconnecting
cables. The circuit breaker resets automatically 3
seconds after the cause of the overload has been
removed and restores the line power. During
short circuit, the LED flashes every 3 seconds.
2
POWER LED
This green LED illuminates if line power is
supplied by the built-in power supply.
3
SYSTEM LINK LED / CHANNEL A
This yellow LED illumines if a channel of another
ASL Intercom system has been connected to the
PS 279 via the System Link connector (see #19)
of the corresponding channel The
“other system”
channel is now the MASTER channel and the
“linked” PS 279 channel the SLAVE channel.
o
The line impedance is now provided by the
MASTER channel and line impedance of
the SLAVE channel is switched off).
o
One can talk, listen and call to and from all
intercom stations on both the MASTER
channel and the SLAVE channel
o
A Mic Mute signal on the MASTER
channel is received by the intercom
stations on both the MASTER and the
SLAVE channel. But a Mic Mute signal
sent from the PS 279 is only received by
the intercom stations on its own channels.
o
A Buzzer Mute signal on the MASTER
channel is received by the intercom
stations on both the MASTER channel and
the SLAVE channel. The Buzzer Mute
button of the PS 279 is now disabled.
See #8 for
“Mic Mute” and #9 for “Buzzer Mute”.
4
SYSTEM LINK LED / CHANNEL B
Same as #3, but for channel B.
5
POWER ON/OFF switch
To switch the internal power supply ON and OFF.
6
BUZZER VOLUME trimmer
7
BUZZER
Indicates an incoming or outgoing call. It is
activated by pushing a CALL button of the PS 279
or a CALL button on any other station on channel
A or B for longer than two seconds, provided the
buzzers are not muted (see #9). The buzzer
volume may be adjusted with the buzzer volume
control (see #6).
8
ALL MIC’S ON/OFF button
With this push button all microphones of the
connected stations can be switched off. Each
user station can activate its microphone again by
pushing its TALK button.
9
ALL BUZZERS ON/OFF button
With this push button all buzzers of the connected
user stations can be muted. The buzzers remain
muted until the Mute button is switched off again.
10
AUX VOLUME controls
These knobs adjust the level of the Aux input
signal to each of the two intercom lines.
11
A / B / HEADSET routing switches
These three push buttons route the Aux signal to
either (1) Intercom channel A and/or Intercom
channel B or (2) directly to the headsets.
12
VOLUME control knobs
To adjust the listen level of the headset, for each
channel separately
