Classic AquaSport

Aquasport Mechanicals - things that need a wrench, screwdriver or multimeter => Electrical => Topic started by: SaltH2OHokie on June 05, 2012, 12:34:25 PM

Title: 4 Batteries, 2 engines and plenty of 12v demand...best sol'n
Post by: SaltH2OHokie on June 05, 2012, 12:34:25 PM

The boat currently has 2 (fresh) batteries with individual on-off switches. I have 2 brand new batteries that I'd like to add in. The fridge and head may get used on anchor as will cabin lights/fans...

I have a guest charger for shore power charging. I know little about how it is wired.

Anybody have a diagram that will show the best way to not leave myself without starting power?

Thanks,
Ryan

Title: Re: 4 Batteries, 2 engines and plenty of 12v demand...best s
Post by: seabob4 on June 05, 2012, 01:11:38 PM

The key is keep the starting batts completely isolated from the house loads when the motors are shut down.  To get the charging abilities of the alternators to the house batts can be done with either a BEP VSR (voltage sensative relay), a Blue Seas ACR (Automatic charging relay), or a Yandina Combiner.  They all work basically the same way, when a charging presence is sensed, and the output voltage is high enough, the relays open and combine the batts to send amperage to all.  Remove the increased voltage source, and they shut, isolating the batts...