User's Manual

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Figure 2.2 – DC Power Distribution from System Surge Protection
The four-approach PCU has the 24VDC power wired from the output of the AC to DC
convertor into a 5-position screw terminal on the left side of the T-bus. This T-bus
has both green and gray connectors. Green T-bus connectors conduct DC power and
RS-485 communications from the left to the right side of the modules. Gray T-bus
connectors conduct only DC power from the left to the right side of the modules.
This means that a device that is attached to a gray T-bus connector will send RS-
485 communications to devices on its right side, but not its left side (see Figure
2.3).
For example, the gray T-bus in Figure 2.2 has its communication lines connected
with the two green T-bus devices on the right side, but not to the one on the left
side.