On the main section, each segment is equipped with twenty optical communications repeaters. These run off direct current fed from Breivika, with the seawater and seabed used for return current. Power is provided through a single-end feed; although supplying from both ends is safer, a single feed was regarded as sufficient. The cables are fed 1.1 ampere at 2,500 volt, fed from two redundant converters. Each repeater has eight erbium doped fiber amplifier pairs. The pairs operate independently of each other, including having their own power supply, allowing for redundancy should one fall out. The repeaters have an estimated lifetime of twenty-five years. The cables are equipped with an ocean ground protection panel to provide isolation and thus hinder damage from lightning.