Page 217 - The ROV Manual - A User Guide for Remotely Operated Vehicles 2nd edition

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CHAPTER 8 Cables and Connectors
Example near neutrally buoyant
RG59 Type coax, 4:
#24 AWG (0.227 sq-mm)
7 strand tin-plated copper DCR at 20C<90 Ω/km polyethylene dielectric
T/C braid, 85% coverage polyethylene jacket Impedance: 75 ohm nominal capacitance at 1khz: 68nF/km atten: <80db/km at 25MHz c/c: BRN, ORN, GRN, VIO
Twisted pair, 4:
#16 AWG (1.22 sq-mm) DCR at 20C<17 Ω/km tin-plated copper with polypropylene insulation rated for 1200 VDC max
two conductors twisted
into pairs and each pressure extruded with polyethylene c/c: WHT+RED, WHT+YEL
WHT+BLU, WHT+GRY
Yellow flotation jacket
Black polyurethane jacket resistant to seawater and oil
KevlarTM strength member: dual layer, counter-wound
PVC/MylarTM binder tapes Water block compound Plastic rod filters
Twisted pair, 4:
#18 AWG (0.96 sq-mm) DCR at 20C<21 Ω/km tin-plated copper with polypropylene insulation rated for 1200 VDC max
two conductors twisted
into pairs and each pressure extruded with polyethylene c/c: WHT+BRN, WHT+RED
WHT+ORN, WHT+YEL
FIGURE 8.49
Overall diameter = 1.535 to 1.575 in (39 to 40mm) nominal Weight in air = 930 lb/1000 ft (1384 KG/KM) nominal Weight in sea = 64 lb/1000 ft (95 KG/KM) nominal
Density = 1.09 to 1.1 gm/cc (1090 to 1100 kg/m3) Breaking strength = 31,000 lb (140 kN) minimum
Peak tension load = 6600 lb (3T) maximum
Bend diameter = 40 in. (1000 mm) minimum Depth rating = 1670 ft (510M) = 725 PSI (5 Mpa) Operating temperature = 28 to 104°F (–2 to 40°C) Storage temperature = –40 to 158°F (–40 to 70°C)
Near neutrally buoyant cable.
• Pairs are unshielded twisted pairs (UTP)
• Flexing cables need stranded conductors
• Shielded versions are rare in the United States
• Industrial versions are another variety
8.8.11 Spare conductors
(Courtesy Falmat.)
Custom cable construction often allows for the choice to either use “filler” strands or spare conduc- tors to maintain a uniform circular cross-section. Fillers are cheaper, but spare wires can be used