Asl intercom PS 278TR User Manual

PRO SERIES

USER MANUAL

FOR THE

PS 278

DUAL CHANNEL MASTER STATION

CONTENTS

1.0 GENERAL DESCRIPTION ...................... 1

2.0 UNPACKING ................................. 1

3.0 MECHANICAL INSTALLATION ................... 1

4.0 MAINS POWER ............................... 2

5.0 FRONT PANEL CONTROLS ..................... 4

6.0 REAR PANEL CONTROLS AND CONNECTORS .... 6

7.0 INTERNAL CONTROLS ........................ 7

8.0 CABLING .................................... 8

9.0 PARTY LINE, TECHNICAL CONCEPT ............. 9

10.0 GUARANTEE ................................. 9

11.0 DESIGN CRITERIA ............................ 9

12.0 TECHNICAL SPECIFICATIONS ................. 10

1.0 GENERAL DESCRIPTION

The PS 278 is designed to be a master unit in an ASL The unique ASL CALL system provides both a flashing red intercom system and can be used in portable as well as LED and a very distinctive and characteristic sound signal. fixed applications. It incorporates a dual channel intercom Only a slight touch of the CALL button will make the LED line power supply, a dual channel headset station, an flash, whilst holding the button for two seconds will activate audio input and uses only 1U of 19" rack space. the call sound signal. In case the sound signal is

undesirable, all buzzers can be muted with the front panel This makes the PS 278 very versatile and ideal for use in 'all buzzers on/off' button. applications where standard microphone cable is available and ease of setup is of paramount importance. Fully electronic switching increases reliability and allows

for : Each channel has a Volume (listen level) control, a Talk - 'soft' microphone ON switching, latched or momentary and a Call button with LED indicators and a sidetone - remote Mic Mute facility. All microphones of stations trimmer. connected to the PS 278 can be muted by pushing a

single front panel button. The intercom line power supply is fully protected and can drive at least 20 beltpacks or 10 speaker stations, or a An Aux input on the rear panel, allows injecting external combination, operating at full power. The power supply is audio signals of line or mic level. When 'mic level' is completely separated from all other functions and in case selected, +30 V phantom power is available at the Aux of power failure the unit can accept line power from an input connector. external ASL power supply. An Aux signal can be routed to intercom line A and/or B, or

directly to the local headset. Since the power supply provides the line impedance, only one PS 278 should be used on the two channels. For As an option, a XLR-6 headset connector can be fitted, driving more beltpacks/speaker stations on these lines an allowing the user to hear channel A + AUX program signal additional power supply booster (PS 285) is needed. on the left headset can and channel B + AUX program

signal on the right headset can. By changing the position Special attention has been paid to the intelligibility of of internally mounted jumpers, it's also possible to hear speech. By applying low noise/high speed circuitry, channel A + B on the left can and the AUX program signal a speech presence filter and a specially designed high on the right can. power headphone amplifier, communication is very comfortable even in environments with a high background noise level.

2.0 UNPACKING

The shipping carton contains the parts listed below. ASL has taken great care to ensure that this product

* The PS 278 reaches you in flawless condition. * 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. returning. With the PS 278 will be a small packet of spare fuses. If any damage has occured, please notify your dealer

Please keep them in a safe place. immediately so that a written claim can be initiated. Please There is also one spare fuse included in the mains inlet. also refer to the guarantee section of this manual.

3.0 MECHANICAL INSTALLATION

A vertical rack space of 1U (1.75", 44mm) is required for required. the PS 278. It is not necessary to provide rear support by extra bracing or shelving. The power supply regulator is mounted on the rear of the

unit, and after a period of time it will feel hot to the touch. Adequate ventilation must be provided by allowing This is quite normal, and should be no cause for alarm. sufficient space around the sides and rear of the unit to ensure free circulation of air. Forced cooling is not

4.0 MAINS POWER

The PS 278 may be connected to the mains power outlet to which other audio equipment is connected. The outlet The wires in this mains lead are colour coded in should have a clean safety earth. Avoid using mains accordance with the following code: power outlets which also power dimmer controlled lighting equipment. green and yellow Earth / safety ground

Before connecting the unit to its AC power source, check if Neutral the mains voltage setting is set in accordance with your brown local mains voltage. The voltage setting is indicated by a Live label on the rear panel.

If a change is necessary, the internal mains transformer correspond with the coloured markings identifying the wiring will need to be reconnected as shown in section 4.3 terminals in your plug, proceed as follows: Mains Power settings. Remember that the AC mains fuse will need to be - The wire which is coloured green-and-yellow must be changed for one of the correct rating as indicated. connected to the terminal in the plug which is marked

The power cord supplied with this unit carries the following coloured green. information label: - The wire which is coloured blue must be connected to

WARNING

This appliance must be earthed

IMPORTANT

blue

As the colours of the wires in the mains lead may not

with the letter "E", or by the earth symbol which is or

the terminal which is marked with the letter "N" or coloured black.

- The wire which is coloured brown must be connected to the terminal which is marked with the letter "L" or coloured red.

Those units that are supplied to the North American market will have an integral moulded 3 pin connector which is provided to satisfy required local standards.

4.1 SAFETY EARTHING

The green-and-yellow wire of the mains cord must always be connected to the electrical installation safety earth or ground. It is essential for personal safety as well for proper operation of the PS 278 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.

The PS 278 employs professionally designed audio input and output circuits which do not require the disconnection of any safety earth for the avoidance of hum loops.

4.2 POWERING UP

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 outlet.

- Turn on the power with the red button. The red overload LED will light up for about 3 seconds, then extinguish and then the green power LED will go on, indicating that the station is active.

4.3 MAINS POWER SETTING

Voltage settings

See also section 4.0 Mains Power

Setting for 115 V AC

1. Red + Green

2. Empty

3. White + Yellow

Setting for 230 V AC

1. Red

2. White + Green

3. Yellow

Mains Fuse

100 - 120V T 630 mA 220 - 240V T 315 mA

(Top View)

Voltage:

5.0 FRONT PANEL CONTROLS

1 POWER ON/OFF switch 7 ALL BUZZERS ON/OFF button

Mains power push button for switching ON and OFF With this button all buzzers of the connected stations the internal power supply. can be muted.

2 OVERLOAD LED 8 AUX VOLUME control knob

This LED illuminates if the internal power supply has This knob adjusts the level of the aux input signal shut off line power due to overload. before it is sent either to the intercom line(s) or to the If the internal power supply is overloaded (too many headset (see also section 5.8). user stations are connected, or short-circuit in the interconnecting cables, or thermal overload), it activates a circuit-breaker which immediately shuts off These three switches route the aux input signal to line power. This circuit breaker resets automatically either: 3 seconds after the overload situation is terminated, 1) Intercom channel A and/or Intercom channel B restoring line power automatically. 2) Directly to the headset During short-circuit, the LED will flash every 3 If the aux is routed to the headset the aux is for local seconds. During thermal overload it will remain on monitoring only, and can not be routed to the intercom continuously. channels. The LED will also come on for a few seconds every time you switch on the mains power.

3 POWER LED

This LED illuminates if line power is supplied by the internal power supply.

4 BUZZER

This buzzer indicates an incoming our outgoing call. It is activated by pressing a CALL button of the PS 278 or a CALL button of any other station on channel A or B for longer than two seconds and the buzzers are not muted (see 5.7). You can adjust its volume with the buzzer volume control.

9 A/B/HEADSET routing switches

5 BUZZER VOLUME trimmer

This trimmer adjusts the volume of the buzzer.

6 ALL MIC'S ON/OFF button

With this pushbutton all microphones of the connected stations can be muted.

+ 11 hidden pages

Asl intercom PS 278TR User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual