1.4 UR HARDWARE
1 GETTING STARTED
1.4 UR HARDWARE
1.4.1 MOUNTING AND WIRING
Please refer to the HARDWARE chapter for detailed relay mounting and wiring instructions. Review all WARNINGS AND
The URPC software communicates to the relay via the faceplate RS232 port or the rear panel RS485 / Ethernet ports. To
communicate via the faceplate RS232 port, a standard "straight-through" serial cable is used. The DB-9 male end is con-
nected to the relay and the DB-9 or DB-25 female end is connected to the PC COM1 or COM2 port as described in the
Figure 1–4: RELAY COMMUNICATIONS OPTIONS
To communicate through the L90 rear RS485 port from a PC RS232 port, the GE Power Management RS232/RS485 con-
verter box is required. This device (catalog number F485) connects to the computer using a "straight-through" serial cable.
A shielded twisted-pair (20, 22, or 24 AWG) connects the F485 converter to the L90 rear communications port. The con-
verter terminals (+, –, GND) are connected to the L90 communication module (+, –, COM) terminals. Refer to the CPU
COMMUNICATION PORTS section in the HARDWARE chapter for option details. The line should be terminated with an R-
C network (i.e. 120 Ω, 1 nF) as described in the HARDWARE chapter.
1.4.3 FACEPLATE DISPLAY
All messages are displayed on a 2 × 20 character vacuum fluorescent display to make them visible under poor lighting con-
ditions. Messages are displayed in English and do not require the aid of an instruction manual for deciphering. While the
keypad and display are not actively being used, the display will default to defined messages. Any high priority event driven
message will automatically override the default message and appear on the display.
L90 Line Differential Relay
GE Power Management