Installation guide
Installation
890USE17100 September 2003 29
Positioning the 
STB I/O
The Advantys STB I/O modules need to be installed in structures called segments. 
A segment comprises a series of interconnected I/O, power distribution modules, 
and either a termination or extension device. These interconnected modules need 
to be inserted in bases which snap together on a DIN rail. These interconnected 
bases form the backplane over which the island passes:
logic power
island bus communications
sensor and actuator field power
protective earth ground (PE)
functional earth ground (FE)
At least one segment, referred to as the primary segment, must be included in the 
island. The primary segment is the first segment on the island and the one that 
contains the NIM. As many as six additional extension segments can be placed on 
the island after the primary segment. Any one segment can support up to 1.2 A 
worth of Advantys STB I/O modules not to exceed the system max of 32 modules. 
Using bus extension cables and modules, an island bus can be stretched to 
distances up to 15 m (49.21 ft).










