Bosch 3.5 User Manual

Page of 498
Bosch Security Systems | 2011-02
2011-02 | Installation and User Instructions | 2 | Introduction
en | 79
3.2.5 Timing
Most calls are broadcast immediately, but calls can be 
time-shifted for broadcasting after completion of the 
original call. This avoids acoustic feedback between the 
microphone and nearby loudspeakers. A time-shifted 
call can also be pre-monitored to check the content 
before it is broadcast and optionally cancelled. This 
feature is only available in combination with a call 
stacker (see chapter 23).
3.2.6 System size
The maximum size of a single Praesideo system is 
limited by the maximum number of nodes in a system, 
which is 63, and the maximum length of the system bus, 
which depends on the actual number of nodes in use. 
See section 31.4 and 31.5 for details. 
The mandatory network controller occupies 3 nodes, 
leaving 60 nodes for other system elements, such as 
amplifiers and call stations. Different models of 
Praesideo power amplifiers have 1 - 4 outputs per 
occupied node and each output can serve an 
independent voice alarm zone. This adds up to a 
maximum of 240 voice alarm zones for a single system. 
This number can be increased by coupling of multiple 
subsystems, as indicated in section 32.6. Alternatively, 
the maximum number of voice alarm zones can be 
increased by using a combination of basic amplifiers 
and multi channel interfaces, see section 9 and 10. A 
multi channel interface occupies only 1 node and can 
drive 14 independent voice alarm zones. For response 
time reasons it is recommended not to use more than 20 
multi channel interfaces in a system. Together with the 
other power amplifiers and call stations, this yields a 
practical limit of some 400 voice alarm zones in a single 
system. 
3.3 Types
3.3.1
Introduction
As mentioned before, Praesideo uses the following types 
of calls:
BGM (background music) calls (see section 3.3.2).
Normal calls (see section 3.3.3).
Emergency calls (see section 3.3.4).
3.3.2
BGM calls
BGM (background music) calls are typically used to 
distribute background music. Their content consists of 
an audio signal from a BGM source, such as a CD 
player or a tuner. By default, BGM calls are partial calls. 
Zones can be added to the routing of a BGM call at any 
time. If an added zone is already in use by another call 
with the same priority or higher, the BGM call will not 
be routed to that zone until it has been released by the 
other call.
3.3.3
Normal calls
Normal calls typically contain live speech and 
optionally chimes and prerecorded messages. The 
content of normal calls is defined by a call macro (see 
section 3.2.3). Normal calls can be partial, non-partial, 
or stacked. 
3.3.4
Emergency calls
Emergency calls are similar to normal calls (see 
section 3.2.3). The major difference is that emergency 
calls put the system in the emergency state and are 
always partial. In the emergency state, Praesideo stops 
all BGM calls and normal calls.