Clever Little Box ZSU-5A User Instructions

User Instructions

ZSU-5A

Zone Selector Unit

The ZSU-5A is a zone selector unit
which, when used with a public address
amplifier, allows up to 5 speaker
zones to be controlled individually or
simultaneously from an external console
microphone or similar unit.

The Unit has an integral signal muting
facility.

The Unit is supplied in a plastic case
which can be wall or table mounted and
is powered either by 240v (120v option)
50/60Hz mains and/or 24v DC.

Introduction:

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By using the hinged quick-release
catch, the enclosures can easily be
closed by hand – use a standard
screwdriver to open.

Description:

• Zone Control:

The zone control section consists of
five DPCO relays which can be selected
individually as required or all together
by activation of the corresponding zone
select terminal(s).

The 100v speaker line signal is
connected to the AMP IN terminals
which are connected to the Normally
Open contacts of each relay. When the
required relay is activated, the amplifier
signal is routed to the corresponding
zone’s output terminals (e.g. +Z1 OUT
and –Z1 OUT in the case4 of Zone 1).

Each Zone also has a set of terminals
marked +Z1 IN (in the case of Zone 1)
which are wired to the Normally Closed
contacts of the corresponding selection
relay. When the relay is relaxed (not
selected) these are connected straight
through to the +Z1 OUT and –Z1 OUT
terminals allowing another amplifier
to feed that zone. This could be used
for background music etc., allowing a
paging amplifier connected to AMP IN
terminals to be routed to selected zones
without disturbing the background music
in the others.

The Zone IN terminals can be paralleled
together as required. If no amplifier
is connected to them they should be
shorted together with a wire link to
prevent crosstalk (i.e. +Z1 IN to –Z1 IN,
+Z2 IN to –Z2 IN, etc.)

Activation of a selected zone is achieved
by connecting the appropriate selection
terminal to 0v (e.g. to activate Zone 1,
the Z1 terminal should be connected to
the 0v terminal, typically via a zone select
switch in a microphone console).

An LED adjacent to the zone relay
illuminates when the zone is selected,
giving a visual indication of its operation
and helping to confirm correct selection
wiring etc.

The terminal marked AC is the All Call
which activates all zones when selected
by connecting it to the 0v terminals.

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• Signal Muting:

A signal muting facility is supplied,
consisting of a DCPO signal relay
which has all contacts brought out to
the ‘SIGNAL MUTE’ terminal group.
The actual muting can be achieved in
several ways depending on the system
requirements, although typically the
signal (from tuner, tape deck, etc.) would
be connected to the common terminal
(C-1) and the normally open terminal
(N\0-1). When the mute relay is activated
the contacts close and the signal is short­circuited. It is important to check that
the signal source from the tuner, tape
deck, etc., is suitably buffered so that
shorting-out the signal will not damage
the source. If in doubt, the relay contacts
should be configured to open circuit the
signal to the amplifier.

As there are two sets of contacts
available, several muting arrangements
are possible. These include muting
balanced signals, muting two separate
signals or using one set of terminals to
trigger a chime.

Activation is achieved by connecting
the MUTE terminal to the 0v terminal on
the zone select terminal group, visual
indication of operation being given by
LED6 ‘MUTE’.

• Signal Wiring point:

When wiring a multizone microphone
these terminals can be used as a neat
and convenient wiring point for the
microphone signal. These can then be
wired to the amplifier mic input.

• DC OUT:

A 24 volt DC fused supply is available
from the Unit, and is suitable for
powering ancillary equipment such as
multizone consoles, line amplifiers, tone
generators, etc. The current available is
limited to 100mA by a fuse (F2).

• DC IN:

The ZSU can be powered from an
external 24 volt power supply via these
terminals. The Unit has reverse current
protection, so that both the mains supply
and the external 24v can be connected
at the same time (e.g. when used in
systems requiring battery backup).

• MAINS INPUT:

Connect the mains input to the ‘L’, ‘N’
and ‘E’ terminals and ensure that the
supply cord is held firmly in place by the
cable clamp adjacent to the terminals.
The Unit is supplied with a standard input
voltage of 240v 50/60 Hz, although it can
be supplied with a 120v 50/60 Hz input
as an option.

• WARNING:

Under no circumstances should any
wiring be carried out to the unit while the
mains power is connected.

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Description: