Is this battery charger dead?

[Steve91T]

Thanks again everyone for your help, I really appreciate it.

From what everyone here has said, I’ve decided I need someone who really knows what their doing. With no inverted, we need the generator running all the time. Can’t make coffee, no fans, baby monitor, or fridge. Because we almost always need ac going, we don’t need some crazy battery bank with an inverter. But it would be really nice to be able to run some fans or make coffee without the generator.

Question, why aren’t these batteries sealed? For safety reasons I feel they’d be better.

Also I figured I’d have 3 starting batteries, one for each engine. How are most boats set up?

Thanks everyone. I’m going to start making phone calls. Next week we’ll be back to the boat and maybe can get someone to take a look so we can come up with a plan.

One more thing. It seems that the mains will charge all batteries but the generator will only by using the battery charger. Does this sound correct?

 

[Bacchus]

I agree with DavidM except the 2 12V look to Gp 31's from their size vs the GCs. They also look like they might be a parallel bank and likely your start bank for main engines.
The 4 GCs are very likely a house bank.
The odd batty? Who knows. Could it have been a gen start batty by itself? If so it should be 12V not 6V but could someone have swapped it in a panic not knowing?

A digital VOM and a long wire (25-50ft) with alligator clips on both ends very helpful tracing / checking continuity.

 

[ranger58sb]

Can’t make coffee, no fans, baby monitor, or fridge. Because we almost always need ac going, we don’t need some crazy battery bank with an inverter. But it would be really nice to be able to run some fans or make coffee without the generator.

Question, why aren’t these batteries sealed? For safety reasons I feel they’d be better.

Also I figured I’d have 3 starting batteries, one for each engine. How are most boats set up?

One more thing. It seems that the mains will charge all batteries but the generator will only by using the battery charger. Does this sound correct?

We've found an inverter useful for exactly that: early morning coffee, late afternoon hors d'oeuvres, etc. without having to start the generator yet. Doesn't necessarily take boatloads of batteries, if you manage it.

Flooded lead acid batteries are often not sealed so you can add water. I've read sealed FLAs aren't great for boat, but I'm not entirely sure why. (Possibly because they're usually starting batteries or at best, dual-purpose batteries?) AGM and gel batteries are valve-regulated (sorta sealed), and that feature is especially useful in the batteries are located in living spaces... plus no special maintenance... at higher costs.

One common setup is a start battery for (each) main and for the genset, plus a housebank. A common variant is to use one of the mains to start the generator.

Given your pics, I'd guess you have twin engines (yes?), an 8D starting battery for each, plus a housebank made up of 4x 6V batteries... plus a rogue 5th 6V battery hanging around doing nothing. (Depending on your engines, I'd guess a single G31 would likely start 'em OK, or a pair of G31s each would certainly get 'er done if necessary.)

We're it me with that sort of setup, I'd consider an Odyssey 31M-PC2150 G31 battery for each engine, an Odyssey 34M-PC1500 for your generator, and a set of 6x (if you have room) Lifeline 6V GLP-4CTs for your house. The 6CT variant if you have available height. That will cost an arm and a leg... and will probably last you a good 10-12 years. With no maintenance.

Another common set-up, especially on U.S. production power boats of the non-trawler variety is a bank of dual-purpose batteries for each main engine and for approximately half of the house loads. Ditto the genset variation.

Can't tell what your last question is about...

-Chris

 

[Steve91T]

Alight I’ve been home and able to digest my battery situation.

Like I said, we’ve had the boat for a couple of years and have had zero problems. Because of a lack of an inverter, we never really run the house batteries down. Maybe if the weather is absolutely perfect will we shut the generator down and just run some lights and the fresh water pump for an evening. So that’s why the charger has been fine...probably acting more like a trickle charger. An inverter would change this.

This morning I was thinking and I remembered that the other day we wanted to run the engines. I tried to start the generator and it wouldn’t crank. It was dead. I was expecting this since I had charger/battery issues. So I then tried to start the starboard main. It cranked up with no issues at all. With the main running, I was able to start the generator and obviously then the port main.

That doesn’t make sense at all.

But I figured it out. I have 4 house batteries and 3 start batteries. The single loan 6 volt battery is actually the generator 12v start battery....that’s dead. I checked voltage and got 6.2v and assumed it was another 6v battery. It’s actually a dead 12v. And it makes sense because that single battery is close to the generator.

I also noticed that if I flipped the switch to just the house batteries, the charger seemed to do just fine. That single 12v battery is probably dragging the whole system down when trying to charge.

Sound about right?

Now...how does an inverter wire up? Complicated deal?

 

[Steve91T]

Sideways pic...not sure why

 

[CMS]

The single loan 6 volt battery is actually the generator 12v start battery....that’s dead. I checked voltage and got 6.2v and assumed it was another 6v battery. It’s actually a dead 12v.

The reason you are getting 6.2V is because it is not a 12V battery but rather a 6V battery...

GC2 is a BCI form factor/size designation it means Golf Car 2 size. GC2 batteries are 3 cell 6V batteries..

225AH @ the 20 hour rate is a standard Ah capacity for a GC2 6V battery. There is no 12V G-24, 27 or 31 battery that has 225Ah of capacity at the 20 hour rate..

 

[Steve91T]

The reason you are getting 6.2V is because it is not a 12V battery but rather a 6V battery...

GC2 is a BCI form factor/size designation it means Golf Car 2 size. GC2 batteries are 3 cell 6V batteries..

225AH @ the 20 hour rate is a standard Ah capacity for a GC2 6V battery. There is no 12V G-24, 27 or 31 battery that has 225Ah of capacity at the 20 hour rate..

Well crap. That makes absolutely no sense then.

 

[Comodave]

Get a certified marine electrician aboard and have him/her go through the boat’s electrical system and make recommendations. Once you have that list you can make some informed decisions on what you want to DIY and what you want the electrician to do. Maybe work out a deal that he/she supervises the work as it is ongoing by you and make sure it is right. Good luck!

 

[ranger58sb]

Well crap. That makes absolutely no sense then.

IF there's space for another GC2 beside that strange one...

and IF the strange one isn't connected to anything (?)...

Perhaps at one time it was one of a third pair for the housebank? Maybe the other one in that pair went south enough to need immediate removal? Leaving it's mate as a puzzle for future owners?

-Chris

 

[DrissZougari]

the number of batteries is really not an issue as it depends on how they connected. He must have two batteries that are in parallel first then in series with the third to get 12v.
Also, I totally agree that he needs a much larger charger (40A-50A) to support all his batteries properly. As far the current charger overheat is concerned, I believe that one of the batteries is bad and he should load test everyone individually.

 

[Steve91T]

Hey guys I just realized I never updated this. So the next time I chased the wires from that single 6v battery. I found its buddy and it was pretty dry. So I topped it off with water, set the charger to charge the house bank. Once it was fully charged I charged the engine batteries. Everything is good now. You guys are right, my charger is too small. But since I almost never run the batteries down, it’ll be ok for now. Now that I know what I have, I can isolate and charge independently if need be.

Thanks everyone.

 

[bluebyu]

Beware,
when a battery is found "pretty dry", I assume the plates were showing?
Often times the batteries life is severely shortened.

 

[Steve91T]

Beware,
when a battery is found "pretty dry", I assume the plates were showing?
Often times the batteries life is severely shortened.

Oh yeah I’m sure years have been taken off it’s life. But it seems to be able to hold a charge and like I said, if I’m not on shore power, I’m running the generator.