Sailor 100, Руководство по установке

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Power cable selection
98-136280-B Chapter 5: Connecting power 5-3
5555
Connecting power
5.2.3 Power cable recommendations
Overview
The ACU is delivered with a power connector (PCB plug-in connector, female plug,
Weidmuller, Part number 1930050000), which accepts wires up to AWG10/6 mm
2
.
• When installing the power cable, install positive and negative supply wires closely
together side by side to keep cable inductance low.
• Ensure that cable inductance for the selected cable at the desired length is less than
50 uH. Approximately 50 m maximum length.
Calculating the maximum power cable length
For 24 VDC operation, the total impedance must be max. 60 mOhm (R
max
for SAILOR 100
Satellite TV with SAILOR Transmodulator and max. 90 mOhm (R
max
) for SAILOR 100
Satellite TV without SAILOR Transmodulator), including the source impedance in the
ship installation (R
source
).
The total impedance is made up of the following:
• Source impedance in the ship installation
• Impedance of the selected power cable
To calculate the maximum cable extension, do as follows:
1. First measure the source impedance in the ship installation as shown in Measuring
the ship source impedance on page 5-2.
2. Find the resistance per meter (Rwire) for the cable type you are going to use.
For 4 mm
2
/AWG 11, the value is 4.8 mOhm/m at 55°C
For 6 mm
2
/AWG 10, the value is 3.8 mOhm/m at 55°C
For other cable types, refer to the data sheet for the cable.
Figure 5-1: Measuring the ship source impedance
SAILOR100IM.book Page 3 Friday, January 18, 2013 10:28 AM