Bosch FPA-5000 - Logical and physical addressing

Modular Fire Panel Planning | en 29
Bosch Sicherheitssysteme GmbH System Information 09.2017 | 11.3 | F.01U.028.089
n
E
= number of elements
ρ = specific resistance of copper = 0.0178Ωmm
2
/m)
R
FET
= FET resistance = 0.7Ω (LSN classic) or 0.35Ω (LSN improved),
I
NE
= average current consumption of elements in[A]
I
trans
= transmission current = 0.012A
I
flash
= flash current = 0.018A
Note that the sum of non-isolated cables must not exceed the limit of 500m. The limit of
500m applies to:
– The lines on the inputs of the following modules: FLM-420-RHV, FLM-420-I2 , FLM-420-
I8R1-S, FLM-420-O8I2-S, FLM-420-O1I1, FLM-420-RLE-S
– The NAC line of the FLM-420-NAC module
– The lines to remote indicators: FAA-420-RI-DIN, FAA-420-RI-ROW
The limit of 500m non-isolated cables doesn't count for the conventional lines of the
FLM-420/4‑CON and the lines connected to the relay contacts and open collector outputs.
Note that the maximum cable length must not exceed 1600m.
Using the Diagram for LSN classic
FET resistance = 0.7Ω, fire alarm cable with Ø0.8mm
Example 1:
You want to know the maximum cable length for a given number of network elements and a
given current consumption (n
E
=50, I
NE
=3 mA). On the X axis, go vertically up at 50 until you
reach the 3mA curve. Then, from the point of intersection go horizontally to the left to the Y
axis and read off the maximum achievable cable length. In this example it is 840m.
Example 2:
You want to know the maximum number of network elements for a given cable length and an
average current consumption of the network elements (L=1000m, I
NE
=20mA). Starting from
the Y axis at 1000, go horizontally across to the right as far as the 20mA curve and then from
the point of intersection vertically down to the X axis. Read off the maximum number of
network elements, in this example it is 8.
Notice!
Remote indicators activated by the detector C point:
A maximum additional cable length of 500m is allowed when using remote indicators (e.g.
FAA-420-RI-DIN/FAA-420-RI-ROW). The total length of installed cable must not exceed the
limit of 1600m.