Siemens SIMATIC Power Line Booster Operating Instructions Manual page 43

The following examples are given to clarify the calculation of the master position. The
position information in this case always refers to the distance from the rail start in traveling
direction.
Special case: Connection via TC module
If you feed in your application through a rail interruption (e.g. lifter) (Page 55) via a TC
module, you must adjust the master position accordingly. The powerline signal is dampened
by the TC module. This corresponds to an attenuation of about 25% of the maximum number
of vehicles permitted and the master position must be moved accordingly. If the rail
interruption is at the segment start, only 40% - 25% = 15% of the maximum number of
vehicles permitted may be located between the entry point and the master.
Examples
Example 1 (PSS application with PLB connection cable ≤ 1 meter)
Segment length 180 m, vehicle length approx. 5 m.
PSS → 1 slave per vehicle → 40 vehicles
Maximum distance from rail start:
40 vehicles (maximum configuration PSS) • 40% • 5 m = 16 vehicles • 5 m = 80 m
Maximum distance to rail end:
40 vehicles (maximum configuration PSS) • 70% • 5 m = 28 vehicles • 5 m = 140 m
→ Position in reference to rail start: 180 m – 140 m = 40 m
Conclusion: The PLB master must be fed in somewhere in the range between 40 meters and
80 meters. The position after about one-third of the distance (equals 60 meters) is ideal.
Example 2 (PDS application with 8 meter PLB connection cable)
Segment length 100 m, vehicle length approx. 8 m.
PDS → 2 slaves per vehicle → 20 vehicles
8 meter PLB connection cable → Reduction of the configuration limit by 40% → The
attenuation through the 8 meter cable corresponds to about 8 vehicles → 20 vehicles -
8 vehicles = 12 vehicles per segment.
The attenuation resulting from the 8 m connection cable affects the area to the right and the
left of the master position.
Maximum distance from rail start:
12 vehicles • 40% • 8 m = 4.8 vehicles • 8 m = 38.4 m
Maximum distance to rail end:
12 vehicles • 70% • 8 m = 8.4 vehicles • 8 m = 67.2 m
→ Position in reference to rail start: 100 m – 67.2 m = 32.8 m
Conclusion: The PLB master must be fed in somewhere in the range between 32.8 meters
and 38.4 meters. The position after about one-third of the distance (equals 33 meters) is
ideal.
Power Line Booster
Operating Instructions, 11/2019, A5E36203125A-AG
Plant planning
3.4 System limits
43