Communications
AC-215x-B Series Hardware Installation Manual
33
6.1.3
Daisy Chaining
You can connect up to 32 panels to a single serial line using a daisy-chain
formation, which is done by drop-down RS-485 wiring (Figure 18).
Figure 18: Daisy Chaining
This can increase the maximum distance from the PC to the last panel in the
chain to 4,000 ft (1,219.2 m).
The first panel is connected directly to the server using an MD-14U converter,
while the second panel connects to the first panel. Additional panels are
connected in the same way, one after another. The server identifies each panel
on the RS-485 network by its address.
At each end of the data line, both where the panel connects to the computer
and on the last panel in the network, a termination resistor of 100–120
Ω
may
be required. Apply the resistor across the L1 and L2 connections.
These termination resistors are especially important in long cable runs.
