Edgetech 4125 SIDE SCAN, Руководство пользователя

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5-13
Most breaks occur around the tow cable termination, or where a previous repair has been made. A cable
break may be found or confirmed by laying out the cable and then attaching an ohmmeter across each
end of the open conductor. Flex the cable first near the termination or repaired section, and then along
its entire length until the break is reached. When flexing, the ends of the broken conductor may touch,
giving a continuity reading on the meter.
5 5.7.3 Locating a Resistance Breakdown
Insulation breakdown is the most difficult fault to locate. Cable leakage is not necessarily located near the
end terminations. However, the area near each termination receives the most abuse and is, therefore,
subject to suspicion. Cutting the cable end until leakage disappears will prove successful in many cases.
CAUTION!
Prior to cutting the cable for any of the above reasons, a careful visual
examination should be made for any signs of physical damage.
With both ends disconnected, the tow cables should measure between 100 Mega-ohms and infinity
between conductors with a 500 VDC Meg ohmmeter. When using a Simpson 260 Multi-meter, all cables,
conductor-to-conductor or conductor-to-shield, should measure infinity. Any leakage on the multi-meter
indicates cable leakage.
5.7.4 Damaged Tow Cable Connector
The tow vehicle includes a safety release mechanism which prevents the vehicle from being snagged.
When the release trips, the tow cable connection to the fish disconnects, exposing the high-voltage pins
to seawater. Pin corrosion will start to occur as long as power is still applied. If the power is not
immediately removed, there may be permanent damage to the connector. Should this happen, the tow
cable will require re-termination.
5.8 Part Numbers for Major Topside Components
The major 4125-P Portable Topside Processor components and their part numbers are listed below:
DESCRIPTION, PART NUMBER
ASSY POWER BOARD 4125 MOD MODEM, 0009300
POWER SUPPLY CHASSIS SW AC-DC 88-264 INPUT 24 OUTPUT 13A 312W, 0007469
WIRELESS BRIDGE / SWITCH, 0007470
CIRCUIT PROTECT HOLDER FUSE 5X20MM 5A 250V, 0003728
CIRCUIT PROTECT HOLDER FUSE BLADE 15A 32V FAST, 0009587