ASL INTERCOM PS 680 User manual

PRO SERIES
USER MANUAL
FOR THE
PS 680
SIX CHANNEL POWER SUPPLY
WITH AUX MATRIX
CONTENTS
1.0 GENERAL DESCRIPTION ..................... 1
2.0 UNPACKING ................................ 1
3.0 MECHANICAL INSTALLATION ................. 1
4.0 MAINS POWER ............................. 1
5.0 FRONT PANEL CONTROLS ................... 3
6.0 REAR PANEL CONTROLS AND CONNECTORS ... 3
7.0 CABLING ................................... 4
8.0 PARTY LINE, TECHNICAL CONCEPT ............ 5
9.0 GUARANTEE ............................... 5
10.0 TECHNICAL SPECIFICATIONS ................. 5
User Manual PS 680 / Issue 1 © 1994 ASL Intercom, Utrecht, Holland.

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland. 1
WARNING
This appliance must be earthed
1.0 GENERAL DESCRIPTION
The PS 680 is designed to be a six channel power supply For each channel separately, the intercom line impedance
in an ASL intercom system and can be used in portable circuitry is installed.
as well as fixed applications. It incorporates two
adjustable auxiliary program signal inputs with a auxiliary Fully electronic switching increases reliability and allows
matrix and uses only 1U of 19" rack space. for remote Mic Mute facility.
The unit is very versatile and ideal for use in applications can be muted by pushing a single front panel button.
where standard microphone cable is available and ease of
setup is of paramount importance. The Aux input at the rear panel, allows injecting external
The intercom line power supply is fully protected and can line. When 'mic level' is selected, +30V phantom power is
drive at least 40 beltpacks or 20 speaker stations, or a available at the Aux input connector.
combination, operating at full power.
All microphones of the stations connected to the PS 680
audio signals of line or mic level into the intercom audio
2.0 UNPACKING
The shipping carton contains the parts listed below. ASL has taken great care to ensure that this product
*The PS 680 reaches you in flawless condition.
*Mains power cable After unpacking the unit please inspect for any physical
*Spare fuses damage to the unit, and retain the shipping carton and
*User manual relevant packing materials for use should the unit need
If any are missing contact your dealer.
With the PS 680 will be a small packet of spare fuses. immediately so that a written claim can be initiated.
Please keep them in a safe place. Please also refer to the guarantee section of this manual.
There is also one spare fuse included in the mains inlet.
returning.
If any damage has occured, please notify your dealer
3.0 MECHANICAL INSTALLATION
A vertical rack space of 1U (1.75", 44mm) is required for The power supply regulators are mounted inside the unit,
the PS 680. It is not necessary to provide rear support by and after a period of time it will feel warm to the touch.
extra bracing or shelving. This is quite normal, and should be no cause for alarm.
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.
4.0 MAINS POWER
The PS 680 may be connected to the mains power outlet
to which other audio equipment is connected. The outlet
should have a clean earth. Avoid using mains power
outlets which also power dimmer controlled lighting
equipment.
Before connecting the unit to its AC power source, check
that the mains voltage, the unit accepts any AC voltage
from 90 - 240 Volts, 50 - 60 Hz.
4.0 MAINS POWER continued
IMPORTANT The wires in this mains lead are colour coded in

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland.
2
accordance with the following code:
green and yellow to the terminal which is marked with the letter "L" or
Earth / safety ground coloured red.
blue
Neutral Those units that are supplied to the North American
brown market will have an integral moulded 3 pin connector
Live which is provided to satisfy required local standards.
As the colours of the wires in the mains lead may not
correspond with the coloured markings identifying the
terminals in your plug, proceed as follows:
-The wire which is coloured green-and-yellow must be
connected to the terminal in the plug which is marked
with the letter "E", or by the earth symbol which is
or coloured green.
-The wire which is coloured blue must be connected to
the terminal which is marked with the letter "N" or
coloured black.
-The wire which is coloured brown must be connected
4.1 SAFETY EARTHING
The green-and-yellow wire of the mains cord must always The PS 680 employs professionally designed audio input
be connected to the electrical installation safety earth or and output circuits which do not require the disconnection
ground. It is essential for personal safety as well for of any safety earth for the avoidance of hum loops.
proper operation of the PS 680 and the other connected
stations. This wire is internally connected to all exposed
metal surfaces and any rack framework into which this
unit might be mounted is assumed to be connected to the
same grounding circuit.
4.2 POWERING UP
Powering up procedure:
-Make sure that the red power switch on the left -Turn on the power with the red button. The red
side of the front panel is OFF. overload LEDs will light up for about 3 seconds,
-Connect the power cord to the rear of the station. will go on, indicating the station is active.
-Plug the other end of the power cord into a See for further installation and operation the concerning
PROPERLY GROUNDED outlet. sections.
then extinguishes and then the green power LED

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland. 3
5.0 FRONT PANEL CONTROLS
1POWER ON/OFF switch
Mains power push button for switching ON and OFF
the internal power supply.
2OVERLOAD LEDS
These LED’s illuminate if the internal power supply
has shut off line power due to overload.
If the internal power supply is overloaded (too many
user stations are connected or short-circuit in the
interconnecting cables or thermal overload), it
activates a circuit-breaker which immediately shuts off
line power. This circuit breaker resets automatically 3
seconds after the overload situation is terminated,
restoring line power automatically.
During short-circuit, the overload LED extinguishes
very shortly every 3 seconds. During thermal overload
the LED burns continuously.
This overload LED also comes on every time you
switch on the main power.
3POWER LED
This LED illuminates if line power is supplied by the
internal power supply.
4ALL MIC'S ON/OFF button
With this pushbutton all microphones of the connected
stations can be muted.
5ALL BUZZERS ON/OFF button
With this button all buzzers of the connected stations
can be muted.
6AUX VOLUME control knobs
These knobs adjusts the master level of the aux (I & II)
input signals before these are routed to the matrix.
7AUX MATRIX trimmers
These trimmers control the volume of each AUX input
as send to that specific channel.
6.0 REAR PANEL CONTROLS & CONNECTORS
8A & B LINE connectors
These XLR-3 type connectors are for connecting user
stations, via standard microphone cable.
There are two connectors for channel A and two
connectors for channel B.
Pin assignments :
1. 0 V / ground shield
2. +30 V power wire
3. audio wire
9AUX INPUT connectors
This XLR-3 type aux input is electronically balanced
and accepts audio levels between -18dBu to +22dBu
on line level, and -38dBu to +2dBu on mic level.
Pin assignments :
1. 0V / ground
2. Signal +
3. Signal -
When mic level is selected, a +30V DC phantom
power is supplied to pins 2 and 3.
10 MIC /
LINE
SWITCHES
With these switches the sensitivity of each AUX input
can be chosen, Mic level or Line level.
When mic level is selected, a +30V DC phantom
power is supplied to pins 2 and 3.
11 MIC GAIN
When Mic level is selected this trimmer adjusts the
sensitivity of the AUX input.
10 FUSE
This fuse protects the PS 680 against severe internal
damage, in case of malfunction in the power section.
To remove the fuse the mains cord must be removed.
It is most important to place the correct fuse in the
holder :
mains voltage
fuse
90 - 240 VAC T 1250 mA
Spare fuses will be found in the small packet supplied
with the unit.

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland.
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6.0 REAR PANEL CONTROLS & CONNECTORS continued
11 MAINS INLET
IEC Mains connector. For correct wiring and operation refer to section 4.0.
12 REMOTE MUTE CONTROL AND AUX OUTPUTS
On this connector are available :
Mic mute controls for each channel seperately
Buzzer mute controls for each channel seperately
Mic mute control for all channels
Buzzer mute control for all channels
The unbalanced AUX signals
Ground (0Volts, pin 1 of each XLR)
+30 Volts power (each channel summed)
To activate a mute, connect the desired pin(s) of the D-25 connector (7-13) to ground (1, 14, 15 or 16).
The unbalanced AUX are available on pins 2 and 3, the signal is the preamplified AUX input signal taken after the
master volume controls (6), before it is send to the matrix.
Use high impedance loads only ! Minimum of 20 K ohms. Lower loads may disrubt the AUX signals to the intercom
lines.
Pin layout of the D-25 :
1Ground (0V)
2Unbalanced AUX signal AUX 2
3Unbalanced AUX signal AUX 1
4+30 Volts (maximum load of 1A !)
5+30 Volts
6+ 9 Volts (maximum load of 50 mA !)
7Mic mute all channels (connect to ground momentary to activate)
8Mic mute channel F (connect to ground momentary to activate)
9Mic mute channel E (connect to ground momentary to activate)
10 Mic mute channel D (connect to ground momentary to activate)
11 Mic mute channel C (connect to ground momentary to activate)
12 Mic mute channel B (connect to ground momentary to activate)
13 Mic mute channel A (connect to ground momentary to activate)
14 Ground (0V)
15 Ground (0V)
16 Ground (0V)
17 not used
18 not used
19 Buzer mute all channels (connect to ground as long as needed to activate)
20 Buzzer mute channel A (connect to ground as long as needed to activate)
21 Buzzer mute channel B (connect to ground as long as needed to activate)
22 Buzzer mute channel C (connect to ground as long as needed to activate)
23 Buzzer mute channel D (connect to ground as long as needed to activate)
24 Buzzer mute channel E (connect to ground as long as needed to activate)
26 Buzzer mute channel F (connect to ground as long as needed to activate)
! Please note that the +9 Volt supply is NOT shortcircuit protected !

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland. 5
7.0 CABLING
For the PRO Series Intercom system the interconnecting
cables are of the shielded two-conductor microphone
cable type and the intercom line connectors are of the
XLR-3 type. Audio and Call signals are on XLR pin 3, DC
power is on XLR pin 2. XLR pin 1 is connected to the
shield of the cable which functions as the common return
for audio and power.
Since the audio signal is transferred in an unbalanced *
way, certain rules have to be obeyed when installing the
cables of an intercom network. This in order to avoid earth
loops and to minimize power loss and the possible effect
of electromagnetical fields.
These rules are:
!! Use high quality (multipair) cable. !! Keep cables parallel as much as possible.
For interconnecting user stations, power supplies and When two (multi channel) units in a network are
accessories in an ASL Intercom network, use high connected by more than one cable, make sure that
quality shielded two-conductor (minimum 2x 0.30 these cables are parallel to each other over the whole
mm2) microphone cable only. distance between those units. When using multipair
In case of a multi channel intercom network, use high cable, parallelism is ensured in the best possible way.
quality microphone 'multipair' cable only, each pair
consisting of two conductors (minimum 2x 0.15 mm2)
with separate shield. Multipair cable should have an
overall shield as well.
!! Use flexible cables.
Use flexible single and multipair microphone cable power supply position) as the center of the star.
instead of cable with solid cores, especially when the
cable is subjected to bending during operation or
installation.
!! Separate cable screen to XLR pin 1.
The screen of each separate microphone cable and/or Intercom cables should cross with energy cables in an
the screen of each single pair in a multipair cable, angle of 90Eonly.
should be connected to pin 1 of each XLR-3 Intercom cables should never be in the same (metal)
connector. Do not connect this cable screen to the trunks with energy cables.
metal housing of the connector or to metal wall boxes
(outlets).
See last page for Earthing Concept.
!! Cable trunks, connection boxes and overall
multipair cable screen to clean earth.
Metal cable trunks, metal connection boxes and
overall multipair cable screen should be inter-
connected and, at one point (the 'central earthing
point') in the intercom network only, be connected to a
clean earth or a safety earth.
See last page for Earthing Concept.
!! Keep metal connection boxes and cable trunks
isolated from other metal parts.
Metal housings for intercom cables and connectors
should be mounted in such a way that they are
isolated from other metal cable and connector
housings and from any other metal construction parts.
*See Party Line, Technical Concept
!! Avoid closed loops.
Always avoid that cables are making a loop. So-called
'ring intercom' should not physically be cabled as a
ring. All cable routes should have a 'star' configuration,
with the central earthing point (usually close to the
!! Keep cables away from electromagnetical sources.
Keep intercom cables away from high energy cables,
e.g. 110/220/380V mains power or dimmer controlled
feeds for spotlights.
!! Place power supplies in a central position.
In order to avoid unacceptable power losses, place the
power supplies as close as possible to where most
power consumption occurs or, in other words, most
user stations are placed.
!! Connect ASL power supply to a 'clean' mains
outlet.
The ASL power supply may be connected to the mains
power outlet to which other audio equipment is
connected. Avoid using mains outlets which also
power dimmer controlled lighting systems.
In case of more complex installations, don't hesitate to
contact us. Please send us a block diagram of the
planned network with a list of all user stations and their
positions, and we are happy to advise you on cabling lay
out.

User Manual PS 680 / Issue 1 © 1999 ASL Intercom, Utrecht, Holland.
6
8.0 PARTY LINE, TECHNICAL CONCEPT 10.0 TECHNICAL SPECIFICATIONS PS 680
ASL's PRO Series offers a complete two way ('full duplex')
communications system.
Users of the system are connected via a 'party line'.
Master stations (with built-in power supply), beltpacks,
speaker stations and power supplies are interconnected
via standard microphone cable. One wire is used as an
audio line, one as a power line and the screen of the
cable functions as earth/return.
Current drive is used for signal transfer. Each station
utilises a current amplifier to amplify the microphone
signal and place it on the common audio line where, due
to the constant line impedance (situated in the power
supply between XLR pin 3 and 1), a signal voltage is
developed which can be further amplified and sent to
headphones or loudspeakers.
This principle has three advantages:
-the use of a single audio line allows several stations to
talk and listen simultaneously.
-due to the high bridging impedance offered by each
station, the number of stations 'on line' has no
influence on the level of the communications signal.
-power and audio to the intercom stations use the
same cable.
The Call signal is also sent as a current on the audio line.
It develops a DC potential over the line impedance which
will be sensed by each station and interpreted as a Call
signal.
9.0 GUARANTEE
This unit is warranted by ASL Intercom to the original end-
user purchaser against defects in workmanship and
materials in it's manufacture for a period of one year from
the date of shipment to the end-user.
Faults arising from misuse, unauthorised modifications or
accidents are not covered by this warranty. If the unit is
faulty, it should be sent in it's original packing to the
supplier or your local ASL dealer, with shipping prepaid. A
note must be included stating the faults found and a copy
of the original suppliers invoice.
THIS PRODUCT WAS DESIGNED, DEVELOPED AND
MANUFACTURED BY:
AMPCO SOUND LAB BV, MAARSSEN (UTRECHT),
HOLLAND
Zonnebaan 42, 3606 CC Maarssenbroek
Tel. [phone] Fax [phone]
Email : [email protected]
POWER SUPPLY
mains voltage range 90 - 240 V AC, 50 - 60 Hz
DC output voltage +30 V +/-5% DC
riple and noise < 11 mV rms
max. output current 2 A continuous, 3 A peak
(each channel)
4 A continues, 6 A peak
(total)
circuit-breaker delay time 0.2 sec.
automatic reset time 3.0 sec.
AUX INPUT
input impedance 30 Kohms (balanced line level)
4.6 Kohms (balanced mic level)
nominal input level -18 dBu to +6 dBu (line level)
-38 dBu to -14 dBu (mic level)
max. input level +22 dBu (line level)
+2 dBu (mic level)
phantom power +30 V DC (mic level selected)
DIMENSIONS AND WEIGHT
width 19" (483 mm)
height 1U (44.5 mm)
depth 250 mm
weight 2 Kg
GENERAL SYSTEM SPECIFICATIONS
intercom line impedance 350 ohms (1kHz)
2.2 Kohms (DC)
intercom line audio level nom. -18 dBu
max. +4 dBu
dynamic range 80 dB
call send signal +2.8 mA
call receive signal threshold +2.4 V DC
supply voltage +30 V DC (12 V to 32 V)
mic mute power interrupt time 0.1 sec
Note: 0 dBu = 775 mV into open circuit.
ASL reserve the right to alter specifications without further
notice.