Table of Contents
Advertisement
LNL-500B Biometric Reader Interface
For Ports 2-3, the following type of RS-485 cable is required: 24 AWG (minimum) twisted pair (with
shields.) The main run RS-485 cable should be no longer than 4000 feet (1219 m), 100 ohms maximum
(Belden 9842 4-wire or 9841 2-wire, plenum cabling Belden 88102, West Penn, or equivalent). The 485
device drop cables off the main 485 bus (to readers and other devices) should be kept as short as possible, no
longer than 10 feet.
Each RS-485 line should contain only 2 terminators, one at each end of the bus. For proper operation, these
terminators should be removed.
Termination
The typical recommendation calls for termination at each end of the line. The link between the LNL-500B
and the biometric devices is fairly short. There may be a need for termination in some unusual cases.
570 —
revision 7
Downstream Device Communication Wiring (Ports 2-3)
Ports 2 - 3
RS-485
2-WIRE
TR2 +
TR2 -
GND
TR3 +
TR3 -
GND
EARTH
GROUND
T-
T+
Advertisement
Table of Contents
