Battery Check

[BruceK]

Originally Posted by C lectric

I've not read the entire thread but your use of SLA, to me at least, is not clear.

Both AGM and GEL are SLA batteries but are of somewhat different construction with different charging needs. Similar but different enough to pay attention to.

The FLA, flooded lead acid, usually has the screw top filler caps for adding water as needed but not always.
There are also some WET cell types, flooded that, although not hard sealed they can benefit from water addition from time to time they too I have seen called SLA.

The SLA are not meant to be opened at all and if you do you have damaged the battery and will shorten its life regardless if it is AGM or GEL.


An AGM and a GEL battery are BOTH SLA. So when you say SLA which type specifically are you referring to, the AGM, the GEL, or the semi sealed FLA.

To me at least it can make a difference in the advice given.

My posts 1,4,6, should help but to summarize, I`m keeping the 2 approx 3yo 8D sealed non AGM non GELs which test fine,until one is unserviceable. And replacing with AGMs, the AGM bowthruster batt, and the 7yo 135Ah/1000cca Genset non AGM non GEL SLA.
Each 8D feeds, presumably via a combiner,one of the peripheral batteries, which both will be AGM.

The Pro Mariner charger is/has,for at least my 3yrs ownership, been set to SLA, not AGM not GEL. My present intention is to leave it that way until one of the non AGM non GEL 8Ds needs replacing, replace them with AGMs, and then set charger to AGM. I know that`s not perfect,it`s highly criticized by some, but it would make more practical/economic sense to dump the 2 "good" 8Ds right now than follow some of the suggestions. Assuming the 8Ds really are "good" because it seems my testing without a graph was deficient. And of course the 2 testing bad I`m replacing could actually be good, despite the 2016 genset simple SLA being so hot I feared possible explosion.
I have not,and have no intention, of opening a sealed battery

[Guilhem]

Originally Posted by BruceK

The marine electrician/boat mover who delivered my boat in 2020 texted me a basic diagram but it doesn`t specify the connection to the 2 peripheral batteries. He did say the diagram meant don`t run on "ALL", without saying why,same as the Boat "Manual". I`ll explore that when I get an electrician onboard.

My guess is the following. When you leave the DC load switch on the All position, it means the output of both batteries are linked together, to feed the DC loads. Consequently, when you're underway, the alternators of both engines are connected to each others, and the current regulator of one alternator will get fried because it's seeing the high voltage coming from the other alternator, instead of a lower voltage from a battery. At least, this is what happened on my boat, one of the alternator wasn't working, and the previous owner always kept the switch on All.
I have since changed the alternator, and leave the switch on 1 on odd days, and on 2 on even days, as recommended by the manual. I will remember the "All" position for the day when an alternator dies and I purposefully want to use the other to charge both engine batteries while underway.

[BruceK]

Thanks Guilhem, it`s good to have an explanation and the GB Manual advice is worth taking. My boat is based on Island Gypsy design,IG was largely copied from GB, so it should be applicable. I just have to remember to switch between 1 & 2!

[SteveK]

Originally Posted by Guilhem

My guess is the following. When you leave the DC load switch on the All position, it means the output of both batteries are linked together, to feed the DC loads. Consequently, when you're underway, the alternators of both engines are connected to each others, and the current regulator of one alternator will get fried because it's seeing the high voltage coming from the other alternator, instead of a lower voltage from a battery. At least, this is what happened on my boat, one of the alternator wasn't working, and the previous owner always kept the switch on All.
I have since changed the alternator, and leave the switch on 1 on odd days, and on 2 on even days, as recommended by the manual. I will remember the "All" position for the day when an alternator dies and I purposefully want to use the other to charge both engine batteries while underway.

I have run on 'ALL' often and not fried my regulator. Fast charge for house bank. An ACR actually automatically places two banks on the 'ALL' position using voltage sensing. What does happen is initial charge amps are double (each ALT output added) until voltage reaches ~13.6 at which point the regulator that is looking for this voltage at a lower amount than the other shuts down and only one alternator continues to charge ALL until full charge is done.
ALT while running/charging cannot have switching or ignition turned off, that can fry the reg. IMO and welcome any corrections.

[Art]

For simplicity of effort and $$$ saving sake:

I'm am an "Ol' Stick In The Mud! - > When it comes to batts. Utilizing an age old, damn easy to deal with and inexpensive way to keep DC power readily available.

Rigs combined, we have 16 WLA Batts. 10 - starter batts / 6 - deep cycle batts

Starter batts last 10 +/- years before they poop out. Deep cycle about the same. 10 years ago... Cost per batt used to be $100 minus... now it's $100 ++

Current [pun intended] 4 deep cycle batts on boat were put in 2018 [5 years ago]. This winter they hold 90% charge after a month sitting idle with no use outflow and no charge input. After 3 to 4 weeks I usually give them an 8 hr. boost to 100% with 60 amp "Professional Mariner" charger [same charger our 1977 Tolly originally came with]. The exact same type deep cycle 4 batts I replaced in 2018 were 10 yrs old.

I get our batts at "Battery Plus Bulbs". East Penn is the batt manufacturer. https://www.batteriesplus.com/produc...cycle/sli31mdc SLI31MDC Duracell Ultra BCI Group 31M 12V 105AH 650CCA Flooded Deep Cycle Marine & RV Battery - $149.99 - 10% discount X 4 = $539.97 [plus tax] -: 10 yrs = $54.00 per yr. = $4.50 per mo. = 1.04 per wk. = $0.15 per da.

Well... you get the $$$ savings, reduced effort picture! Right??? LOL

PS: I also drive... with all of em cherry: 1967 Buick Wildcat / 1985, std. cab, 1-Ton, 4WD, 4 spd. standard shift, Chevy Cheyenne truck / 1992, std. cab, 1-Ton, 4WD, 5 spd. standard shift, Ford XLT truck / 1998 Ford Explorer XLT SUV.

Wife has a low mileage, beautiful, classy, fast, comfortable, sexy, great sound system, jet black, multi passenger, dash board touch screen with its original self cooling-cooler between the two rear seats! 2014 Lincoln MKT SUV - With - All kinds of computer crap running all its features.

Within last couple years the Lincoln cost over $4K computer chip repairs. During same couple years my 4 old cherry rigs cost less that $1000.

I really enjoy being: "Ol' Stick In The Mud"!

[BruceK]

Originally Posted by SteveK

I have run on 'ALL' often and not fried my regulator. Fast charge for house bank. An ACR actually automatically places two banks on the 'ALL' position using voltage sensing. What does happen is initial charge amps are double (each ALT output added) until voltage reaches ~13.6 at which point the regulator that is looking for this voltage at a lower amount than the other shuts down and only one alternator continues to charge ALL until full charge is done.
ALT while running/charging cannot have switching or ignition turned off, that can fry the reg. IMO and welcome any corrections.

Is this a feature of your current boat, and/or the GB, and/or all twin engine boats?
I`ve also run on "ALL" without alternator damage, on 2 boats. But I also take notice of material appearing in a GB Manual. And the(sketchy) Manual for my Integrity, and the advice of my boat delivery marine electrician, both saying not to run on ALL.

[SteveK]

Originally Posted by BruceK

Is this a feature of your current boat, and/or the GB, and/or all twin engine boats?
I`ve also run on "ALL" without alternator damage, on 2 boats. But I also take notice of material appearing in a GB Manual. And the(sketchy) Manual for my Integrity, and the advice of my boat delivery marine electrician, both saying not to run on ALL.

All boats with a 1-2-all switch will have this in all position. That is bat 1 or bat 2 or both.
On the current boat it has an on/off switch labelled combine.
Yes I have had it on all boats with two separate banks.

[BruceK]

Originally Posted by SteveK

All boats with a 1-2-all switch will have this in all position. That is bat 1 or bat 2 or both.
On the current boat it has an on/off switch labelled combine.
Yes I have had it on all boats with two separate banks.

Is this response the experience of others?
On the peripheral battery replacement, the new Optima 34M now powers the bowthruster to a lusty growl. The genset battery is disconnected, its 1000cca AGM replacement charged at home pending install. The battery charger is relaxed, relieved of trying to maintain the two unmaintainable batteries.

[BruceK]

Yesterday we removed the old 135ah/1000cca sealed VLRA genset battery. IG/Integrity batteries sit in a fibreglass box with cover lid. Battery out, a lot of white powder was evident, presumably sulfur from dried leaked sulfuric acid. The box kept the material contained and was undamaged.
It`s not long since, on 2 occasions, I checked the battery. First time it tested ok, 2nd time it was hot and tested bad,query catastrophic failure in between. I`ve heard of several explosions of these batteries on my marina,with messy results, we were lucky to catch it.
They might be "maintenance free" but they should not be inspection free.

[BruceK]

I searched for a Manual for my ProNautic1240P charger. At some point I`ll change the setting from Sealed LA to AGM. I need to know how, and it`s good to have the Manual.
I found the charge parameters:
Conditioning Voltage: same for SLA/AGM, 14.4V
Auto Maintain Voltage: SLA 12.8-13.6: AGM 13-0-13.4V.
It`s the latter which differs. AGM sits within the SLA parameters but not as low or as high. My 2 AGMs are charging off the SLAs so they get what the SLA`s have or if the charger operates, what the SLAs are getting.
It`s neither perfect nor, to my mind, dramatically bad. My Battery Gauge reads 13.4V usually, and when charging around 14.5V. I`ll replace the SLAs with AGMs at the first sign of tiredness, so far they continue to test "Good".

[ranger58sb]

Originally Posted by BruceK

Auto Maintain Voltage: SLA 12.8-13.6: AGM 13-0-13.4V.
It`s the latter which differs. AGM sits within the SLA parameters but not as low or as high. My 2 AGMs are charging off the SLAs so they get what the SLA`s have or if the charger operates, what the SLAs are getting.
It`s neither perfect nor, to my mind, dramatically bad.

We had a 1260P, and IIRC we could program one profile with exact voltages we wanted.

I was only using it for one bank of AGMs, though, so more juggling wasn't necessary.

-Chris