Bosch Appliances Home Security System 3.5 User Manual

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Bosch Security Systems | 2011-02
Praesideo 3.5 | Installation and User Instructions | 7 | System Hardware Installation
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the power consumption scales with the output power 
in an almost linear way.
The idle power consumption is specified in the 
amplifier section of the manual and should be 
divided by 48V to get the idle supply current for that 
amplifier, and then multiply by 24 hours to get the 
required battery capacity in Ah for that amplifier in 
idle state.
For EN54-16 systems, the use of the amplifier power 
save mode is not permitted.
During emergency calls often an alarm tone is 
broadcast. The maximum level of such a tone is 
-3dB, corresponding to half the rated output power. 
The -3dB power consumption of the amplifiers is 
also specified in the technical data section. Divide by 
48V and multiply by 0.5 to get the required battery 
capacity in Ah for that amplifier for a maximum 
level alarm tone during 30 minutes. In case the 
amplifier is only partly loaded the battery capacity 
can be reduced accordingly. In case live speech or 
spoken messages are used instead of tones, the 
capacity can be halved again because the rms output 
level of speech is typically < -6dB for full output. In 
case an alarm tone has less than 100% duty cycle (i.e. 
contains a silence period) the capacity can be 
reduced accordingly. In case the output level is less 
than the maximum output level, again the capacity 
can be reduced accordingly.
For spare amplifiers only the idle current 
consumption should be taken into account.
The power consumption of all units that are powered 
by the network controller is given in section 33.2. 
Add up for all connected units, divide by 48V and 
multiply bij 24.5 hours to get the required battery 
capacity in Ah for these units.
Take the sum of all calculated battery capacities and 
multiply by 1.25, as a margin to compensate for 
battery capacity loss due to aging of the batteries.
To reduce the risk of making errors, it is strongly 
recommended to use the Praesideo Power Requirement 
Calculator.
33.4 Power 
sources
By default, the only power source in the system is the 
network controller. Each system bus connector on the 
rear of the network controller provides 55 Watt.
If more power is needed, external power supplies must 
be used to feed the system. The following units have a 
provision for connecting external power supplies:
PRS-NSP Network Splitter. An external power 
supply that is connected to a network splitter only 
adds power to the tap-offs. 
PRS-FIN(S), PRS-FINNA Fiber Interface. An 
external power supply that is connected to a fiber 
interface only adds power to the Praesideo system 
bus.
LBB4433/00 Call Station Kit. An external power 
supply that is connected to a call station kit only 
adds power to the call station kit.
PRS-CSI Call Station Interface. An external power 
supply that is connected to a call station interface 
only adds power to call station interface and 
optionally to the connected remote call station (kit).
PRS-CSR Remote Call Station. An external power 
supply that is connected to a remote call station only 
adds power to the remote call station and optionally 
to the connected call station interface.
PRS-CSRK Remote Call Station Kit. An external 
power supply that is connected to a remote call 
station kit only adds power to the remote call station 
kit and optionally to the connected call station 
interface.
The amount of Watt provided by an external power 
supply is calculated as follows:
Note
If you create a redundant ring and you do not 
use additional power supplies, you can connect 
up to 55 Watt to the network controller. This is 
to ensure that when there is a fault in the 
network close to one of the system bus 
connectors of the network controller, the other 
system bus connector can still feed the entire 
network.
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