Units that intermittently draw high current
(such as a windlass
or your compressor) are best wired directly to a battery
bank, with an appropriately-sized breaker or fuse close to the battery
. This is because if you fed them through a breaker on your DC panel, the current
surge and transients from the heavy load are more likely to disturb electronics
like your instruments, and also because the fewer connections you have in a high-current path, the fewer the points of potential failure.
There's no reason you cannot use 10-2 duplex wire of the appropriate gauge to feed the compressor
Originally Posted by Paul Elliot
For that matter, I don't understand why they should care about a cable with properly done in-line connections.
Every connection is theoretically a point of failure. Connections are subject to the quality of materials used, the workmanship, and the effects of corrosion
. Most electrical
codes don't permit
any connections in places where they cannot be inspected, and I try to follow that goal in boat wiring
as well. The higher the current, the greater the risk posed by bad connections.