FX16 Master Controller Technical Bulletin 15Connection Details for I/O Expansion (XT91/XP91 Modules) on LocalExtension BusFigure 7 displays the connection details for XT/XP modules on a localextension bus.Figure 7: Connection Details for the XT/XP ModuleConsider the following information when you work with theconnections details for the XT91/XP91 Modules:• Maximum XT modules are 4 x XT91D00 (or XT-9100).• Maximum bus length is 1200 m (4000 ft).• You must set appropriate N2 bus serial address on each XT module.• Install a repeater (for example, RP-9100-810x) to regenerate theRS-485 signal. You install the repeater in case more than31 N2 devices are connected on the local link extension bus and/orthe local link extension bus length is more than 1,200 m (4,000 ft).• Install 220-ohm end-of-line resistors at each end of the XT-Bus linewhen the bus length is greater than 100 m (330 ft). When the buslength is less than 100 m (330 ft), insert only one 220 ohm resistorat the FX16 Master Controller end only.XT91D00 XT91D00
