SailNet Community - View Single Post - ANL fuse size at battery
View Single Post
post #3 of Old 12-05-2010 Thread Starter
Senior Member
orientalnc2010's Avatar
Join Date: Oct 2007
Location: oriental NC
Posts: 145
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 10
Thanks Maine Sail for the insightful and clear response.
The inspection of battery wiring was necessary to become familiar with my factory install as I am adding a windlass. I believe that this is relevant to my thread in that;
I have run 2/0 cables from the windlass directly to the house bank, with a 110 amp breaker in the feed. The windlass is 1000watts and draws 85 amps according to the manufacturer. The total length of the run is 52' round trip.
My question concerns using my emergency cross over connector that is in my blue seas panel. My blue seas panel has a rotary switch for engine battery, on or off. There is a switch for my house battery, actually it is a 100 amp breaker.
Then there is an emergency crossover switch, looks like a windup key and has two positions, on and off. ( I have auto combiner, ACR or echo charger by choice at this time)
Simple and easy to follow but what happens if my house bank has some sort of catastrophic event and I have to use my emergency crossover.
Lets say it I start dragging anchor at 2AM because a strong front moved in. The house bank is completely useless for some unknown reason at this time, so I start the engine. I'm now operating all systems on my start battery. Group 27 100 AH
I need to use the windlass to reset the anchor. I have my running lights on but that's it. When I start the windlass all of the current will be going through 2AWG from my aux battery to my emergency crossover switch then back down 2AWG to my house battery, aprox 20' (the panel is 10' one way from the batteries). The current then has to travel the 2/0 cable to the windlass, 50' round trip. Would 2 AWG stand up to this temp situation?
I would think that 10% voltage drop may be OK for this "not likely" circumstance.

Am I over thinking this? I like to prepare for the worst case because this is what happens when you are least expecting it.
Attached Images
File Type: jpg battery wiring schematic.jpg (41.0 KB, 54 views)

PSC 31 #125
Oriental, NC
One of the two happiest days in a sailors life
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
orientalnc2010 is offline  
Quote Share with Facebook
For the best viewing experience please update your browser to Google Chrome