Setting up for House Battery -> looking for feedback on loads

[ESGWheel]

I plan on setting up a dual battery system in my 2005 Larson 228 LXi Bowrider with a VP 5.0 GXi-E as a spring project.

Its more for a peace of mind vs. significant house loads. There are no trolling motors or bow thrusters. The most going on the ‘house side’ is the stereo and the chart plotter and it’s not one of those high amp stereos. But we do sit at anchor for most of the day with the stereo going and my wife keeps the chart plotter on to monitor anchor drag.

The batteries will both be the lead acid and of the exact same size / model for this set up using a Blue Seas Add-A-Battery Dual Circuit System kit 7650 that come with the 7610 ACR and battery switch.

I have reviewed a lot of posts on what loads to which battery and this is what I have come up with and looking for feedback. Thanks.
Start Batt Loads:

• Starter
• Engine electronics
• Trim Pump
• Blower
• Bilge pump (higher i.e., will come on only if House Pump overwhelmed)
• Nav Lights
• Gauges
• Horn

House Batt Loads:

• Interior lights
• Dock Lights
• Chart Plotter
• Stereo
• VHF Radio
• USB Ports
• Induction Charging Stations
• 12V Cigarette Lighter Sockets (used to blow up rafts)
• 2nd Bilge Pump (will come on first)

 

[alldodge]

Interior lights - depends on what type and how many lets say 20W
Dock lights - won't be used just sitting, unless your talking under water lights or other type
Chart plotter - depends on which one/size lets use 3A or 36W
Stereo - just the head unit or has some kind of small amp?
VHF - up to 7A if transmitting or maybe 80W
Inductive phone charger - 30W for the new type
12V outlet - depends on how often it's used
2nd Bilge pump - depends on size maybe 50W

 

[cyclops222]

What do you want to cause a SURPRISE. Of a no starting of the engine condition ?
I never put anything on with the engine starting battery. Easy to trouble shoot a sudden bad starting engine battery.
Simply go to BOTH BATTERIES of the big battery switch & head for the home dock.

If you have a sudden death of the engine battery ? I would remove & tape up the only heavy cable attached to the engine battery. Tape over the bare cable end for safety. Switch the big battery switch both. and drive home safely.

 

[dingbat]

What is the goal of your rewire?

In my case, the goal is redundancy. Brought about by a situation on a friend’s boat where we lost his starting battery (shorted cell) 20 miles out of port in the waining hours of a mid-February day

The motor is wired to the switch, not a battery. That way I can use either, or both batteries to start the motor.

Primary battery, deep cycle:
Trim tabs, bilge pumps, primary navigation instrument feed (chart plotter and VHF) and navigation lighting.

Secondary battery, deep cycle:
Stereo, spreader lights, wash down and bait well pumps, power feed to fish finder, radar, back up navigation devices and accessories.

 

[ESGWheel]

Sorry for delay… life happens.

For the wattage of the loads, I have complied a listing in a spreadsheet but not yet complete. My thinking about the outlined split was an initial draft and was wondering what others have done, so Dingbat, thanks for your listing.

Which brings me to the “why”. Frankly with this little runabout we use only on lakes, it’s not really needed. And I have never been stranded due to a low battery. But to answer the question: my goal is three-fold:

1. just for the fun of it > I like to tinker and doing this appealed to my childish self.
2. our boat is docked at a lake that is 3 hrs distant to us (unmanned marina, no power and no cell service), which keeps me slightly on edge when we are away. In another post, someone suggested if a dual battery have dual bilge pumps as well, one on each battery and setup to come on at different water heights. That really appealed to me and I will do that as part of this project.
3. for the experience and lessons it will teach me > I like to help others with their issues and have started diving into the electrical side. But a dual battery set up is something I have no experience with. My goal is that with this project completed I will be better positioned to help others. Walking the talk so to speak.

 

[KD4UPL]

I have always just had 2 dual purpose batteries and a switch. All loads on one or the other. I use 1 battery 1 day and the other battery the next. If 1 dies I can switch to the other but I've never needed too.
We just boat on lakes as well and mostly just daytime. I see no reason for a dedicated house and start battery.