89 mid cabin battery wiring

[mrrudely]

this has probably been covered before but here goes
I have two starting batteries and one deep cycle battery
It seems as if the original set up is to have the start batteries also serve as the house batteries
If so does anyone know the reasoning for this?

I'm thinking of having the deep cycle serve as the house battery
Would this be as simple as disconnecting the starting batteries from the breakers and connecting the deep cycle to both breakers?

IMG_4423.jpg (119.56 KiB) Viewed 11597 times

[mrrudely]

attached photo is existing set up

[prowlersfish]

attached photo is existing set up

The reason they used one starting battery as the house is because it worked. At least for most owners and factored in that the Genset would be used a lot. Got confused at first as you labeled the starting batteries as staters lol. I think when new you may have also had a generator battery also.

The issues I see with your setup are as follows. I see no charging of the house battery from the engines when underway. Also the windlass is normally run off a starter battery and used with the engine running.

What exactly are your house loads and how long? just overnight or days on the hook?

[BobCT]

I went through the same process on my mid cabin but left the start battery/house setup as is but upgraded to group size to 31’s (they fit fine) and use dual purpose batteries to handle the house loads. The biggest draw is my cabin fridge so I installed a switch to share the load between the two batteries. After 7-8 hours I toggle over to the other battery if I’m on the hook overnight. No issue running lights (all LEDS now), head, TV’s etc.

In addition, I added a 3k inverter (no generator) and four 6v golf cart batteries. That’s dedicated to my wet bar fridge, stereo/amp, underwater lights and my 4000 GPH bilge pump. I also added a dedicated AC outlet in the cabin for coffee maker, toaster oven, etc., on demand and a panel switch so I can run my microwave. I’ve done this up to two days without an issue. Basically everything on the boat works normally except AC and stovetop. This is probably n/a for you since you have a generator but this is a good option for someone who doesn’t or has 1-2 day overnights and would rather not run it.

I have a pair of jumper cables in case I ever needed to jump from the house bank to a start battery but will probably never need them.

Bob

[mrrudely]

thanks guys
all good info
so as not to cover too much
one step at a time
does anyone know how to connect my house battery to one of the engine alternators? (good suggestion, prowlersfish)
also I think I need a new alternator any suggestion as to how may amps?

[RWS]

Whatever you do, suggest a DIRECT battery monitor on the dash.

No guessing with this, saved my a$$ a few times

Helps you manage ALL systems.

https://shop.opticsplanet.com/blue-sea- ... PlEALw_wcB

This was one of the first mods I did

BEST !

RWS

[prowlersfish]

thanks guys
all good info
so as not to cover too much
one step at a time
does anyone know how to connect my house battery to one of the engine alternators? (good suggestion, prowlersfish)
also I think I need a new alternator any suggestion as to how may amps?

You can use one of these so an engine can charge the house bank. https://www.bluesea.com/products/catego ... ing_Relays

Alternator maybe 70 amps ? You really did'not say so i I am not really sure of your house load and bank size.

[Boppy]

Do you have the AC/DC wiring schematic that came with the boat? Would be a big help with your questions if you did. If not contact Bob to see if he can sell you one. Suggest you run a list of the DC amp hour draw of your house needs to get a better idea of the size of the deep cycle battery you need. I’ve had good results with lead acid deep cycle ones from Walmart but recently changed to 2 100 amp hour lithium batteries wired in parallel and powered by solar panels. I still use lead acid starter battery for the single engine

[mrrudely]

prowlersfish -
I moved the windlass to the Port start battery
can't quite decide between blue sea ACR or Victron Argofet Battery Isolator
Boppy-
I have the wiring diagram
I am using a 100 amp hour deep cycle for the house battery

I would like to take the house load off of the port start battery and move it to the deep cycle
there are two wires coming out of the main breakers on either side of the paralleling solenoid
I suspect one is the alternator and one is the house?

[Boppy]

OK, now here goes again. Been having trouble posting my reply even though my UN and PW are accepted by the website. I think you need to figure out what your house bank needs are. 100AH deep cycle may be enough but if it’s lead acid then you’re really only supposed to discharge it down to 50% of capacity before it needs recharging. Any lower and you shorten the life of the deep cycles. So, you’re getting 50AH of capacity. Your fridge may be the biggest AH drain on the system. Finally, please take a look at the Trojan wiring diagram that came with the boat. That should be a big help in figuring out how to wire the deep cycle so it’s dedicated to the house needs. Also, you could jump the positive of the port engine battery to the positive of the house battery, using proper fusing, and then both batteries would be charged by the alternator when underway.

[prowlersfish]

I think you need to figure out what your house bank needs are.

Also, you could jump the positive of the port engine battery to the positive of the house battery, using proper fusing, and then both batteries would be charged by the alternator when underway.

Agree on figuring out the needs. As far as jumping the 2 unless it is switched or you use a ACR you would discharge both.

[mrrudely]

thanks guys
I have attached a new proposed wiring diagram
I moved the anchor windlass to the port start battery
I disconnected the port start battery from the breaker and connected the house battery in its place
I added a ACR (or battery isolator) joining the port battery with the house battery
I have the inverter charger connected to the house battery
I have the protect charger connected to the port and starboard batteries (using only two banks of the three available)

I don't yet know how big of a bank I need for the house but with this setup I think I can add as needed

Does the positive of the genset charge whichever battery it is connected to?

[prowlersfish]

Yes the genset will charge the battery it is hooked up to. It is very low output.

[mrrudely]

hey guys
here is my new proposed wiring diagram
I moved the genest to the starboard start battery

I came across the following in the manual and I am wondering what it means and if it is of any concern.

GENERATOR BATTERY:
"This consists of one or two 12 volt maintenance free batteries. It is used exclusively for starting and operating the generator and is recharged automatically when the generator is operated.
CAUTION: Do not make any connection to these batteries while they are connected to the generator, or damage to the generator will result."

My thinking is that the engine start batteries would be a good bet for having power to start the generator and I would then have a dedicated battery for my inverter.

Separately the port start battery runs the cabin lights so I am thinking that should be replaced with a dual purpose battery when the time comes.

Any comments would be greatly appreciated.
rr

[Boppy]

Suggest you check out deep cycle for your house bank not dual purpose but that’s just my opinion. Figure out how much your house bank needs by adding up the amps used per hour when nothing is charging that battery and get a deep cycle to meet or exceed that by another 25%