[C320-list] In-line fuse on battery cables

[Scott Thompson]

I'm having some trouble understanding why blowing these fuses would stop 
the alternator from charging the batteries. Did you move the battery 
switch to #1 or "both" to test that?

On 9/14/2020 12:33 PM, SARA SCHROEDER wrote:
> I had reached out to the group regarding recommendations on battery charges, echo-chargers and solar panels.  As a reminder I have two 4D deep cycle batteries, did not have a starter battery or echo-charger and my batteries were either not being fully charged or were losing capacity. After doing research, my helper and I ganged the two 4D batteries together into one house bank which became bank #1 and installed a new starter battery which became bank #2.  We also installed a new ProMariner ProNautic 12V 40 AMP battery charger.
>
> After a full weekend away from the dock, this set up turned out to be an epic failure.  The batteries were not being charged at all - either by the new charger or the alternator.  Upon further inspection we discovered that both the alternator and the new charger were blowing the 20amp in-line fuse located in the positive battery cable. We considered just putting in a larger fuse but Platt Electric recommended we not do this.
>
> We undid everything and reverted back to the factory settings.  One 4D is back to house bank #1 and the second 4D is house bank #2.  The starter battery and echo-charger are on hold for the moment.  We installed new fuses in both positive cables, fired up the new battery charger and my batteries finally started getting a charge.  At first the ProNautic was pumping in about 40amps but this quickly came down to about 20amps.  After about 30 minutes of charging my helper reached down and touched the in-line fuse casings. They were shockingly hot. We could not really even touch them.  I stayed at the boat to monitor them and after about 3 hours I could touch them and the cables themselves were "slightly" warm but not hot.
>
> I suspect the fuse housings are original which makes them 20 years old.  Does anyone have these round in-line fuse housings or is it just me? Have you had problems with them failing or replaced them? If you replaced them what did you use?  Thanks as always!
>
> Sara
> Wandering Star
> 2000 / #707