These photos are a prime example showing why chafe protection is a safety concern on boats. This incident happened when these conductors were running through a bulkhead with no chafe protection. Boats are constantly flexing and moving. Over time the rubbing against the wood bulkhead broke through the insulation on these wires. The picture with the chafed red wire is the positive wire running from the windlass solenoid to the windlass. The picture with the white wire shows a two conductor wire running to the solenoids: one positive and one negative. The negative cable shorted out with the positive running to the windlass. Luckily the red cable was only hot when the windlass was being used, as it was on the downstream side of the solenoid.
Heat and wood bulkheads can lead to a catastrophic fire on a boat. Some kind of chafe protection should be used whenever routing wiring around anything that may cause physical damage to the insulation. This can be accomplished with; split loom, grommets, silicone, electrical tape, conduit, ect. These are all inexpensive ways to avoid much larger problems in the future. Supporting conductors is equally important. ABYC standards state that wiring must be supported throughout their entire length or at least every 18”.