132
C
ABLING INTERFACES
CHAPTER 4 INSTALLATION
Figure 4.36: S bus, short, V-shaped
Figure 4.37: S bus, long
Figure 4.38: S bus, point-to-point
Greater distances (up to 8km) can be achieved using a standard commercial S bus extension.
Restrictions
The maximum number of terminals per S bus is further restricted by the power requirements of the termi-
nals and their supplementary equipment:
The number of terminals is the sum of the power requirements of the individual terminals and the power
available on the S bus.
Table 4.26:Power balance on the S bus
Power available [W]
S bus short
5
1
1. These values are based on a wire diameter of 0.5 mm.
S bus, long
3.5
a