2.0
GENERAL DESCRIPTION
The BS 287 is a dual channel power supply to be
used in an ASL intercom system. It can safely
drive up to 15 Basic Series beltpacks operating at
full power.
The dual channel power supply is fully protected
against wiring mistakes (reverse power), short
circuit or dangerous thermal condition.
Should one of these conditions occur, the unit
shuts down. Once the fault condition has been
removed, the BS 287 resets automatically and full
power is restored.
An Aux input – with ground lift switch - at the rear
panel allows injecting external line level audio
signals into the intercom lines. On the front panel
are Aux volume controls, one for each channel.
3.0
MECHANICAL INSTALLATION
For the BS 287 a vertical rack space of 1RU
(1.75”, 44mm) is required. 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
rear of the unit; after a period of time it will feel
hot to the touch. This is quite normal, and should
be no cause for alarm.
4.0
MAINS POWER & SAFETY EARTH
Connecting to mains power
The BS 287 may be connected to a mains power
outlet which provides 100 – 240 V AC, 50-60 Hz
and at least 60 watts. The outlet should have a
clean earth. Avoid using mains power outlets which
also power dimmer controlled lighting equipment.
The wires in the mains lead are color coded:
green/yellow: Earth / safety ground
blue:
Neutral
brown:
Live
In case the wires in the mains lead do not
correspond with the colored markings identifying the
terminals in your mains plug, proceed as follows:
•
The wire which is colored green/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.
•
The wire which is colored blue must be
connected to the terminal which is marked
with the letter “N” or colored black.
•
The wire which is colored brown must be
connected to the terminal which is marked
with the letter “L” or colored red.
Safety Earth
The green/yellow wire of the mains lead 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 BS 287 and connected
stations. In the BS 287 the green/yellow wire is
connected to all exposed metal surfaces. Any rack
framework into which this unit might be mounted is
assumed to be connected to the same grounding
circuit.
5.0
FRONT PANEL CONTROLS & CONNECTOR
1
POWER ON/OFF switch
Mains power on/off push button
2
MAINS POWER LED
This LED illuminates if the unit is switched on.
3
AUX VOLUME control knobs
To adjust the AUX input level to each of the
intercom lines A & B
