Electrical Question

[Gina Marie]

Adding 4 electric reels to my 45C. Two on the flybridge and 2 on the cockpit.

Spec. 12V 5amp at idle
12V 10 to 30 amp in use.

I have two 12V panels one on the bridge and plan on the using the main in my engine room starboard side for the cockpit.

I need a shut off when not in use and I quess two 30 amp breakers per setup

Panels are already full

Can I jump off the main feed to the panels thus creating a new subpanel if not what should I do, Safety first.

Thanks Gina Marie

 

[Pete]

The basics of safety says you fuse any wire leaving a panel. Thus on your existing bridge panel, you probably have a main breaker that feeds all the individual circuit breakers. The switched side of the main breaker likely feeds a buss bar that jumpers all the hot sides of the other breakers. You want to attach to this buss bar to have the safety of the main panel breaker. On your main starboard engine room panel you likely have some fuses in the lower section of the panel. If there is a open position, use this and get a ANL 75 amp fuse. If all the fuse positions are being used, my approach would be to attach to an existing fuse that is identified for a function that you would not be using at the same time as the reels, like the anchor windlass. Not the ideal solution, but a solution. Just remember, the +12 feed wire and negative wire you take off these panels to your sub panels, must be fully rated for the current of the circuit breaker/fuse that it is attached to in the existing panels. This guarantees that if you develop a short, the circuit breaker/fuse will do its job.

Pete

 

[REBrueckner]

A slight variation on the above suggestion would be to combine two breaker/fuse circuits already in use into one breaker/fuse and free up one for your reels. For example, move the positive wire from an oil change pump fuse from it's own breaker/fuse to perhaps a "searchlight" breaker/fuse....very unlikely those two would be in use simultaneously...Just label the new connection correctly because a few years from now you won't remember what you moved where...at least I forget....

 

[NAN-PO 41]

I always label any new wiring that I add to the boat. I also change or add it to the wiring diagram in the owners manual. Usually I just add a page to the book so that the original diagrams don't get too cluttered ( Kind of like a sub diagram ). I find this really helps me at a later date as I suffer from CRS. ( Can't Remember S##t )
Fred

 

[GOLE IV]

You can make another panel feeding from the feeders of each panel or disconnect switch, but as per ABYC DC standard and practices there is a limitation of the unprotected length of the feeder wires. ( for general service, not for cranking motor)
For feeder wire running out of the battery to the Over current protection device, the maximum recommended length is 72"
For feeder wire running from the battery disconnect switch to the over current protection is 7" or 40" if contained is a sheath or enclosure.

the best practice never run service wire without over current protection and never exceed the wire rating on the OCP.