Battery problem thoughts much appreciated!

[a64pilot]

Most installers if they are good, will choose the AGM setting, and not try to program actual voltages even if the charger will. Close, but no cigar.
Most normal installers, will just install the batteries and walk away, lord knows what the charger is set for, and it’s good for business as he’s coming back for another set of batteries in another year, two at most.

[misfits]

Originally Posted by a64pilot

Some batteries you can, Lifeline in their manual has a chart for SOC for batteries when under a 20 hour to 50% discharge load, and an 8 hour to 50% load. The numbers are very close to being the same.
Never have understood what a SOC chart that requires the batteries to be under zero load for hours is good for, what cruising boat disconnects their banks for hours, regularly?

I hear ya but the fla trojans I have do require a minimum of 6 hours rest, 24 is recommended. If one has a battery monitor, you know the story.

The OP has a problem with his chargers. Evidently they were not large enough, configured correctly or have failed. Either way, glad I'm not him. 800 AH of batteries, that's going to be painful.

[kenbo]

Originally Posted by a64pilot

Most installers if they are good, will choose the AGM setting, and not try to program actual voltages even if the charger will. Close, but no cigar.
Most normal installers, will just install the batteries and walk away, lord knows what the charger is set for, and it’s good for business as he’s coming back for another set of batteries in another year, two at most.

So a GOOD installer will not look at the manufacture's spec for charging and simply flip a couple of dip switches and call it a day?

No wonder I have so many customers.

[john61ct]

Voltage is a very poor indicator of SoC.

Huge variations in the relationship with charge vs discharge, depending on current and duration.

Not only is their correspondence different for each model even at rest,

it changes as bank SoH declines.

Not completely useless, but a very rough ballpark even if you do try to take those variables into account.

[roland stockham]

Originally Posted by kenbo

You can and should equalize Lifeline AGM's

OK I may be out of date on this one, lifeline does indeed recommend equalization.
presumable the recombination technology for minimizing water loss has improved. Water loss though remains the limiting factor on all sealed batteries. Any water used cannot be replaced and at some point the battery will die because of water loss. I also don't want to hijack the thread into a discussion of battery types.

[a64pilot]

Originally Posted by kenbo

So a GOOD installer will not look at the manufacture's spec for charging and simply flip a couple of dip switches and call it a day?

No wonder I have so many customers.

Not really. I was just trying to say that many installers don’t know as much about your system as you should know.
In truth I don’t trust most people to do things, as I’ve not run into a Maine Sail or others that clearly have forgotten more than I’ll ever know. They are out there, I know they are, just haven’t run into them.
The OP will become quite knowledgeable about his battery bank, if he hangs out here, and reads Main Sails knowledge base etc. when he gets there, he won’t trust others to program his chargers either.

However his problem really could be as simple as a loose ground, here is hoping so anyway.

[a64pilot]

Originally Posted by roland stockham

OK I may be out of date on this one, lifeline does indeed recommend equalization.
presumable the recombination technology for minimizing water loss has improved. Water loss though remains the limiting factor on all sealed batteries. Any water used cannot be replaced and at some point the battery will die because of water loss. I also don't want to hijack the thread into a discussion of battery types.

You mistreat a Lifeline and it will hiss at you, short it out for example.
That is of course the valve releasing gas, which has to mean water loss.
However under normal charging and discharging and no real altitude changes, I think they are really sealed, the valve doesn’t open.

[a64pilot]

I know the Concorde aircraft battery very well.
I’m certain that the Lifeline battery is actually an offshoot of the Concorde aircraft battery. There may be some differences of course, but I believe the Concorde came first, and it is by far the best normal aircraft battery there is.
Normal meaning lead acid.

[john61ct]

Concorde Battery Corporation is the family owned and operated company that makes Lifeline brand AGMs.

Just in case anyone mistakely thinks they had anything to do with the Concorde aircraft, that is not the case.

When AGM was new, the top vendors thought low charge rates and equalization were a good idea.

Over the years Lifeline and others discovered that high charge rates were good for longevity, between .2 and .4C as a minimum.

They also stopped recommending equalization, except for Lifeline.

That exception is, according to many, a good reason to buy them over the other brands.

Both Odyssey and Northstar are however also fine products.

[mitiempo]

Originally Posted by roland stockham

......I would not be suprised to find the shunt if fitted after the rotary switch.

The other thing I would check is the 3 way rotary switch. These are notorious failure points, Ideally bin it and get something better. Boat builder love to fit them as they are cheap and simple but they really have no place on a cruising boat. Power levels are to high and they regularly fail. They also present a significant fire risk because as they fail they create high resistance and start generating heat.

Should be replace with either a 0v drop splitter or a diode block and smart regulator

The shunt for the Victron BMV will not be near the switch as it is in the negative lead, first connection after the post assuming it is installed correctly.

A 3 way rotary to me means a 1/2/both switch for selecting a particular battery bank for a given use. While they are certainly not my favorite, my preference being a simple on/off for each use, I don't see how they can be replaced with a diode splitter and smart regulator.

Ideally the charger output should be direct to the house bank. Each other battery can be charged with an ACR or other type of zero loss battery to battery charger. If that is what you mean I stand corrected.

The the op - the Phoenix @ 50 amps is way too small for your battery bank, enen without the 30 amp load and charging of other batteries on board. The company that recommended that charger was very wrong on sizing it. With the 30 amp load what is left is basically a trickle charge for a battery bank that large. Rolls recommends bulk charging be 25% of capacity @ the 20 hour rate. For your 600AH bank that is 150 amps ignoring the 30 amp load. The minimum size charger I would suggest is 100 amps.

[Bermuda Forte]

Following- ‘need to know what the OP finds and the solution.

[fguptill]

It looks to me as if your charger is incorrectly configured. For AGMs, battery voltage while under charge should be around 14V.

[NYSail]

Check your ground..... I had issues when first bought boat last season. Turned out to be a corroded ground wire from battery to monitor terminal. Also ground on starter had signs of rust. Once I replaced wire and cleaned everything I had no issues.

[hzcruiser]

While measuring the batt voltage at the terminals I'd also check if any connections get noticeably warm after say 10 mins of your 30A load. If there is a drop of say 500mV on one connection it will dissipate 15W which will cause a distinct temp increase.

[NYSail]

Originally Posted by Stu Jackson

Yup, an oxymoron.

Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.
Check the ground at the engine.

Then check all the rest of the connections. All of them.

By check, this means:

Remove them, pull on the lugs, check the condition of the wire into the lugs, if OK add heat shrink if it isn't there.

Good luck.

Stu is 100% right..... check the grounds! he directed me (NYSail)
Good luck!