Roberts Gorden 10081601NA Rev H 12/11 - Manual (Page 42)

ROBERTS GORDON
®
ULTRAVAC™ C ONTROLLER I NSTALLATION M ANUAL
36 of 62
5.5.1 Repeater
If the RS-485 communications wire length is above 4000' (1219 m), a repeater must be used to extend the
signal. The repeater can also be used to install in different methods:
• To extend communications beyond the standard 4000' (1219 m) limitation. See Page 36, Figure 21.
• To add parallel branches of ROBERTS GORDON ® ULTRAVAC™ controller communications bus wiring.
See Page 37, Figure 22.
NOTE: The maximum number of ROBERTS GORDON ® ULTRAVAC™ Controllers that can be installed is
242.
FIGURE 21: Repeater External Wiring
Description Part Number
Repeater URVRP