Dual Battery ... Wiring fail or I just don't understand?

[zul]

Well, I've wanted a dual battery switch for years on my old boat and just never got it done. Purchased a new-to-me boat last month. What a beauty! Anyhow, this boat has a pro looking dual batt switch, pro looking wiring and 2 brand new batts. The boat sits in a garage 3 hours away from me where I cannot get a trickle on it. I plan to take one battery home each month, trickle charge it, take it back to the boat and swap out for the other batt to trickle.

So, right now, I've got one batt at home and one in the boat. Back at the boat to do some work on it, no power. The battery in the boat reads 12.6v. No lights, no chirp when I turn the key. No power. I've moved the switch from "1" to "2" to "All" and get nothing.

Is this how it should be wired? It seems to me that having one batt removed should allow the other battery to work without any problems?? Is it wired incorrectly or is it supposed to be wired in a loop like this? Makes me think if one battery goes dead the second battery will not fire the motor?

 

[dingbat]

Well, I've wanted a dual battery switch for years on my old boat and just never got it done. Purchased a new-to-me boat last month. What a beauty! Anyhow, this boat has a pro looking dual batt switch, pro looking wiring and 2 brand new batts. The boat sits in a garage 3 hours away from me where I cannot get a trickle on it. I plan to take one battery home each month, trickle charge it, take it back to the boat and swap out for the other batt to trickle.

So, right now, I've got one batt at home and one in the boat. Back at the boat to do some work on it, no power. The battery in the boat reads 12.6v. No lights, no chirp when I turn the key. No power. I've moved the switch from "1" to "2" to "All" and get nothing.

Is this how it should be wired? It seems to me that having one batt removed should allow the other battery to work without any problems?? Is it wired incorrectly or is it supposed to be wired in a loop like this? Makes me think if one battery goes dead the second battery will not fire the motor?

Both battery ground cables get tied together on battery #1

I'm going to take a wild guess that you unhooked the ground cable (from Battery #2) from the system when you disconnected battery #1.

No ground, no power

 

[tpenfield]

^^^^ This.

The ground wires are probably 'daisy chained' and you disconnected the ground to the second battery when you unhooked the first battery.

 

[flashback]

I did exactly that several years ago and then had to scratch my head for a bit!

 

[airshot]

Any chance of using solar chargers on your boat in storage to make charging less hassle ?

 

[KD4UPL]

You must loving hauling batteries around. I'd just leave them in the boat with the switch off. They will be fine for several months without needing to be on a charger.

 

[poconojoe]

I also don't see the need to keep bringing a battery home for charging.
If you turn the battery switch to off, you should be good for quite a while.

The solar charger idea is a good suggestion. It certainly can't hurt.

 

[zul]

Any chance of using solar chargers on your boat in storage to make charging less hassle ?

I thought about that ... but the garage is very large like an airplane hanger. My 'spot' is in the middle. Oi!

There is the new invention of 'Solar Generators' (Jackery is the most popular) where I believe I could hook it up, let it 'trickle' up the boat batts for a few hours. No tools, less hassle. So, working on that plan now. These new Solar Generators will have lots of potential use in the boating world!!

 

[flashback]

Sounds like a plan let us know how it works out.

 

[dingbat]

I thought about that ... but the garage is very large like an airplane hanger. My 'spot' is in the middle. Oi!

There is the new invention of 'Solar Generators' (Jackery is the most
popular) where I believe I could hook it up, let it 'trickle' up the boat batts for a few hours. No tools, less hassle. So, working on that plan now. These new Solar Generators will have lots of potential use in the boating world!!

Using a battery maintainer as a “bulk” charger after use results in degraded performance and shorten life expectancy, especially for a starting battery designed to be discharged and immediately replenished.

Manufactures recommend charging lead-acid batteries at a rate between 10% to 25% of the battery’s Ah rating.

Size your solar charger accordingly

 

[Bt Doctur]

 

[airshot]

Using a battery maintainer as a “bulk” charger after use results in degraded performance and shorten life expectancy, especially for a starting battery designed to be discharged and immediately replenished.

Manufactures recommend charging lead-acid batteries at a rate between 10% to 25% of the battery’s Ah rating.

Size your solar charger accordingly

That also depends on how low the charge is on your battery. If battery has only dropped 20% then a 1 amp charge will work, but if your battery is down 40% then a higher amp charge is needed to bringbthe battery back to 100%. The trickle charger is more of a maintainer than to recover a battery from a deep discharge. When storing my batteries for the long winter, I make surevthey are fully charged then switch them to a maintainer for storage. Has added extra life to my batteries by doing this !!!

 

[dingbat]

When storing my batteries for the long winter, I make surevthey are fully charged then switch them to a maintainer for storage. Has added extra life to my batteries by doing this !!!

I top off my batteries (110 Ah deep cycle x 2) and leave them in the boat when I put the boat way in December. Typically don't charge them again until the end of March.

Been doing this forever. The set of batteries I replaced last Spring as PM had 2010 and 2011 date codes on them.

I get more "bang for the buck" with proper battery sizing to restrict discharge to no more than 50% and charging the battery back up as soon as possible.

I'm a coastal fisherman. Pretty common to run 40-50 miles a day fishing. The install of an ACR to take advantage of the charging opportunites did wonders for my battery life.

 

[Grub54891]

I just make sure they are charged fully in the fall then unhook the grounds and leave them in the boat. In the spring I hook them up and start the boat up. Usually get 5-6 years before replacement, but when they get that old, they still work, I just replace them for the reason they are getting old. It gets down to -40 sometimes up here.