Cable - Kamstrup M-Bus Master MultiPort 250D Installation And User Manual

4.3.1

Cable

The cable resistance and capacity must be as low as possible. The thicker the cable, the lower the resistance. The
thicker the cable, the higher the capacity.
An M-Bus cable must as a minimum be able to handle 50 V and 500 mA.
Diameter (mm ø)
0.5
0.65
0.8
1.0
1.13
1.26
1.39
1.6
Examples of resistance in copper cable.
Please note that the resistance in copper depends on its purity. The purer the copper, the lower its resistance.
LiYY 2x0.34 mm
Current load
Cable resistance
Capacity
J-Y(St)YY
Current load
Cable resistance
Capacity
Examples of cable types.
Kamstrup A/S • 5512853_C1_GB_01.2017
Cross section (mm
0.20
0.33
0.50
0.79
1.00
1.25
1.52
2.0
2 2x0.50 mm
Max 4.5 A Max 6 A
56 Ω/km 39 Ω/km
110 nF/km 120 nF/km
2x0.60 mm
-
65 Ω/km
120 nF/km
Resistance in Ohm
)
2
per 1,000 metres
90
53
35
23
18
14
12
8.7
2 2x0.75 mm 2
Max 10 A
26 Ω/km
120 nF/km
2x0.80 mm
2 2
-
37 Ω/km
100 nF/km
M-Bus Master MultiPort 250D
Length in metres per Ohm
11
19
29
45
57
71
87
115
2x1.0 mm 2 2x1.5 mm
Max 12 A Max 18 A
20 Ω/km 12 Ω/km
120 nF/km 120 nF/km
2
19