Raisecom
RC1104-FE-4W (A) User Manual
3 Preparing for installation and connecting cables
Raisecom Technology Co., Ltd.
8
–
DC: -48 V
Voltage range
–
AC: 85–264 V
–
DC: -36 to -72 V
3.9 Actual line measurement
The common telephone wire (wire diameter: 0.4 mm/0.5 mm/0.6 mm) is used as the
connecting line. Use a multimeter to measure the impedance of the loop after the carrier
makes the telephone wire into a loop.
Table 3-5
Comparison table of wire diameter and impedance
Wire diameter
Loop impedance
0.4 mm
270 Ω/km
0.5 mm
170 Ω/km
0.6 mm
120 Ω/km
Length of subscriber line (transmission distance) = (loop impedance/resistivity)/2
Table 3-6
Comparison table of single-line pair rate and transmission distance
Single-line pair rate (Kbit/s)
Transmission distance of 0.4 mm wire (Km)
192
6.5
512
5.9
1024
5.0
2048
4.5
2304
4.3
5696
2.6
11392
1.4
14976
0.7
The table above provides the rate of the G.SHDSL single-line pair. The rate of the dual-line
pair doubles that of the single-line pair. Moreover, the comparison table lists the result tested
in the laboratory without consideration of the interference noise. In actual applications, the
transmission distance may vary due to the line quality and interference. So this table is just for
your reference.
