Black Box ME738A-F Manual Del Usuario página 11

SHM-NPR 2-WIRE
Signal Ground (Pin 7) lines are connected, the SHM-
NPR will still work. Control signals are not required.
In compliance with RS-232C and V.24 standards, the
SHM-NPR generates both positive and negative
signals—no matter what the state of Transmit Data,
which can be constantly high or constantly low.
Table 2-1 shows the transmission ranges you can
expect with the SHM-NPR 2-Wire. The figures are only
approximate; the conditions in your own installation will
determine how far you can actually transmit.
Table 2-1. Approximate transmission distances
Gauge
Distance
Figure 2-1 shows how to connect two SHM-NPRs.
8
19 AWG
1.4 miles
(2.3 km)
Center
GND
Figure 2-1. A 2-wire connection.
22 AWG 24 AWG
0.8 miles 0.6 miles
(1.4 km) (1 km)
RG-62 Coax
1 mile
(1.6 km)
Center
GND