Bosch Appliances 3.5 8: Output A and B in the same area, 9: Output A and B in separate areas, en

Praesideo 3.5 Installation and User Instructions 4 Amplifiers

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The loudspeaker lines can be connected in three different ways depending on the level of supervision and redundancy required.

If loudspeaker lines A and B are in the same area, connect the loudspeaker lines as shown in figure 10.8.

This method has no redundancy. Both A and B relays are normally closed.

•If a line fault is detected by the supervision boards in one of the groups, the group remains live.

•Only if an overload is detected, the affected group will be switched off. A fault event is generated.

Spare In	EOL
	A
Pilot	B
	EOL

figure 10.8: Output A and B in the same area

This method has full supervision and redundancy. The A and B relays are normally closed and supervision boards (see sections 12.2.2 and 12.2.3, indicated with EOL) are connected to both the A and B groups.

•If an amplifier overload occurs, then the multi channel interface will control the A and B relays to isolate the overload and keep the other group working.

•If a line fault is detected by the supervision boards in one of the groups, the affected group will be switched off. A fault event for group A or group B will be generated.

If loudspeaker lines A and B are in different locations, connect the loudspeaker lines as shown in figure 10.9.

Spare In	EOL
	A
Pilot	B
	EOL

figure 10.9: Output A and B in separate areas

If loudspeaker lines A and B must form a class-A loop, connect the loudspeaker lines as shown in figure 10.10

Spare In	A
	B
Pilot	EOL

figure 10.10: Class-A loop from output A to B

Both A and B outputs use the same loudspeaker group. The A relay is normally closed and B relay is normally open.

•If a line fault occurs, detected by the supervision board (EOL), the relay B closes and a fault event is generated to indicate the switch over.

•If the cable is broken, the A output gives power to all loudspeakers that are before the break, the B output gives power to all loudspeakers to the other side of the break.

•If a short-circuit or overload causes the line fault, the amplifier generates a fault event.

Bosch Security Systems 2011-02