Heat Loss Calculation - Bosch PRAESENSA Installation Manual

PRAESENSA
Device Device elements
PRA-SCL System controller
+ per active port (2)
PRA-CSLD Call station
+ per active port (2)
+ per extension PRA-CSE (3)
+ with alarm option
PRA-ES8P2S Ethernet switch
+ per active RJ45 port (2)
+ per active SFP port
+ PoE load
PRA-AD604 Amplifier (active, idle)
Amplifier (active, low power)
Amplifier (active, full power)
+ per active port (2)
PRA-AD608 Amplifier (active, idle)
Amplifier (active, low power)
Amplifier (active, full power)
+ per active port (2)
PRA-AD608 Amplifier (active, idle)
Amplifier (active, low power)
Amplifier (active, full power)
+ per active port (2)
Minimum required backup power capacity of UPS [Wh]
Minimum output power capability of UPS [W]
5.5

Heat loss calculation

To be able to calculate the required cooling capacity of a cooling system for a technical room
with equipment to stay within temperature limits of the equipment, the heat production must
be known and the maximum ambient temperature that the equipment is allowed to operate in.
The maximum ambient operating temperature of PRAESENSA rack‑mounted devices is 50 °C
(122 °F). The generated heat is the energy that is dissipated and released as heat by the
equipment in the room. Energy is power multiplied by time, so the longer a certain amount of
power is dissipated in the room the more heat is generated. The amount of energy is
expressed in joule, calories or BTU, British Thermal Units. The amount of power is expressed
in watt. By definition 1 joule = 1 watt x 1 second. Furthermore: 1 kJ = 1.055 BTU = 4.184 kcal.
The PRAESENSA system controller just dissipates some power that is taken from the power
supply. This power turns into heat. The same is true for the call stations, but they are typically
placed outside the technical room and do not contribute to heat production in the room.
PRAESENSA power amplifiers dissipate some power that is taken from the power supply, but
when announcements are made or music is played through the system, the output power of
the amplifiers is dissipated in the loudspeakers and the cabling to the loudspeakers. Because
the loudspeakers and most of the cabling is not in the technical room with the equipment, this
Bosch Security Systems B.V.
Power Time in
taken from quiescent
mains [W] mode [h]
4.2 24
2 x 0.5 24
5.0 24
2 x 0.6 24
3 x 0.1 24
1.5 24
8.4 24
2 x 0.5 24
1.2 -
PRA-CSLD -
39 24
64 -
250 -
2 x 0.4 24
48 24
88 -
274 -
2 x 0.4 24
48 24
88 -
274 -
2 x 0.4 24
Installation manual
System composition | en
Time in Power x
alarm time [Wh]
mode [h]
0.5 103
0.5 25
0.5 123
0.5 29
0.5 7
0.5 37
0.5 206
0.5 25
- -
- -
- 936
- -
0.5 125
0.5 20
- 1152
- -
0.5 137
0.5 20
- 1152
- -
0.5 137
0.5 20
4254
45
Maximum
power [W]
4.2
2 x 0.5
5.0
2 x 0.6
3 x 0.1
1.5
8.4
2 x 0.5
-
-
-
-
250
2 x 0.4
-
-
274
2 x 0.4
-
-
274
2 x 0.4
823
2019.11 | V1.00 |