Unit installation

MR-2900 Installation Manual
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Table 5: Maximum Capacitance for Network Baud Rates
RS-232 Network Wiring
RS-232 Network wiring uses three (3) wires between each panel (see
Figure 27). The COM1 of each Unit is connected to the COM2 of the next
Unit. MR-2944 Annunciator Units are connected the same as the Control
Unit. Wiring is polarity sensitive.
MR-D1010R Wiring
Refer to LT-2048 MR-D1010R Fiber Optic Module Installation Instructions.
Baud Rate Maximum Capacitance Maximum Network Nodes
9600 100 nF 254
4800 220 nF 254
2400 470 nF 254
1200 680 nF 200
Notes:
• Ensure that only one COM 2 is connected to each COM 1. If two or more are connected, the
network segment does not work.
• The wire length limit for RS-232 is 20 feet (6m) in conduit, in the same room. For systems using
modems, this is the maximum distance between the panel and the modem.
Figure 27: RS-232 Network
Wiring