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Old 04-13-2021, 08:41 PM   #1
WinnyJourney04
 
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Cool 05 Journey AUX BATTERY SWITCH won't switch

My 2005 Winn Journey 34H has a Aux Battery Disconnect Switch (rocker switch) on RH instrument panel. One day it failed to disconnect the house batteries which is had done faithfully for last 7 years. When rocker switch is pushed to left the coach batteries do not disconnect and 12 volts to coach remains on although is seems to be at a reduced voltage as the lights dim a little.

I assumed it was the cutoff solenoid which sounded okay (clicking sound when switched was depressed). I replaced it anyway just to be sure. No change. I also replaced the solenoid (Trombetta) that allows the engine alternator to charge both house and chassis batteries. This didn't change things.

If I disconnect the chassis batteries (physically remove battery cable) then the Aux Battery switch "does" disconnect the coach batteries as it should (lights go off, etc).

The only thing left is the switch on the dash but that doesn't seem that it could be the cause.

Somehow chassis battery power is getting to the coach circuit.
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Old 04-13-2021, 08:54 PM   #2
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Here's my 2004 Itasca Horizon 40AD Solenoid Diagrams that may help you diagnose your troubles.

I have worked these over to the best of my ability to make sure the BDS and the Boost Solenoid wires are properly identified, but I have not verified this myself with a volt meter.

Your 2005 may also have a slightly different wire label chart, but it could also be the same as mine. Anyway, these diagrams should help.

====

Also, the Trombetta Boost Solenoid is activated by the boost switch on the dash. It's a momentary switch that joins the engine battery to the house battery, but it does nothing (as far as I know) to pass amps from your alternator to your house batteries.

For that I believe your coach came with a B.I.R.D device and these have been known to go bad. In which case you just remove it and my advice would be to install a KeyLine VSR.

Here's the thread I just posted some information to the other day if you want more information on it:

https://www.winnieowners.com/forums/...rt-360787.html
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Old 04-13-2021, 11:32 PM   #3
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Quote:
Originally Posted by imnprsd View Post
...
Also, the Trombetta Boost Solenoid is activated by the boost switch on the dash. It's a momentary switch that joins the engine battery to the house battery, but it does nothing (as far as I know) to pass amps from your alternator to your house batteries.

For that I believe your coach came with a B.I.R.D device and these have been known to go bad. ...
This is incorrect. The Trombatta Boost Solenoid IS activated when the momentary 'Battery Boost' switch is pressed, but it is ALSO activated whenever the engine is running (there is a 'run-only' power connection to that same switch which is connected to the solenoid when the switch isn't being pressed). This is how the coach batteries are charged by the alternator when the engine is running.

The Journey never had a BIRD device installed. Ultimate Advantage/Freedom coached DID have a BIRD device, as do some more recent coaches, but not a 2005 Journey/Meridian (or Vectra/Horizon).
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Old 04-14-2021, 07:31 PM   #4
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Thumbs up

Thanks for all the help. I believe I have found the problem. The problem was in the Trik-L-Start charger that came with the coach. It is wired from the Coach side of the battery disconnect relay and the chassis battery side of the Trombetta and charges the chassis batteries when connected to shore power.

It is wired correctly per manual but I am guessing that a diode or similar circuit in it has failed allowing current to pass from chassis battery around the disconnect relay an into the coach circuit when it should be a one-way circuit (coach battery to chassis battery). This explains why all the coach lights dimmed (thin wires) when I pressed Aux Batter switch to off.

I took the Trik-L-Start out of the circuit and everything works as it should.

I should have started there first but look at it this way. Sooner or later either or both the Trombetta and Disconnect relay were going to fail. So now I'm good for a few more years and have spares to boot.

Thanks again for all the help. My first time posting.
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Old 04-14-2021, 07:47 PM   #5
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Here's the source for a new Trik-L-Start. I would recommend replacing the failed one--it does a good job of keeping the chassis batteries charged up (and the latest 'Mega' 'Rev F' version charges at 10A, twice the 5A of the original version).
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Old 04-14-2021, 08:06 PM   #6
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cbeierl: Your explanation on how the boost solenoid is powered is more detailed than other posts I have read by you and others.

I have been trying to produce an accurate circuit diagram borrowing bits and pieces of information on these solenoids for 6 months now.

And now, last week, I just picked up my coach from storage, and when I get to a place where I plan to stay for 1 or more weeks I will get out my multi-meter and verify the diagram posted above and your comments about the Boost Solenoid always being on.

Do you know, in your RV, how many amps the alternator is passing to the house batteries when the house batteries are at ~12.0V (near 50% SOC). Do you know? Have you measured it?

Why?

Well, I have been an advocate of the KeyLine VSR, because I know it works great. And today I put a clamp meter on my Keyline lead to my house batteries and I measured 35.7A of alternator juice after I spent the night boondocking... with my house batteries at 12.0V. ...Then I started my engine and held the RPM at 1000... and as I said I measured 35.7A to the house batteries. An that's a pretty good charge from the alternator only.

And under these same conditions, I measured 12.2A on the Keyline wire going to my engine batteries.

What's interesting about this is that the alternator is connected the the engine battery and then to the house battery thru the KeyLine VSR.

The alternator is rated at 160A with about 50% efficiency.

My point is that the engine batteries were nearly full in the morning, and that's why they were only accepting 12.2A.

I.e., batteries that are full resist charge more than when they are at 50% SOC.

And since current will follow the least path of resistance, most of the current that is, goes to the house battery bank because it was low on charge.

Note: The alternator was putting out 13.9V, as viewed on my y RV EMS display.

This verifies what I see after 4-5 hours of driving too. I.e., I would say my engine alternate contributes about 80-120AH to my house battery bank on a trip of this length; and I would say I get the same amount of 80-120AH on an average sunny day from my solar controller with 400W on my roof.

Consequently, with the KeyLine VSR and my 400W of solar power I always reach my next destination with a full house battery bank.

==> Now how does the stock system work? You are saying the Boost Solenoid coil is always energized so the engine batteries are DIRECT connected to the House batteries? If that is the case, what regulates the amount of current flowing from the alternator to the house batteries?

I don't see how that makes sense, because if you have a short in the house battery side then it will drain the house batteries and also drain the engine batteries, if the Boost solenoid is always "on".

This does not seem like a good design to me, but maybe I'm missing something. Can you explain what I am missing here, and if you see any errors in the circuit diagram above please let me know.

Alternatively, this is a fact: My 2004 Itasca Horizon was shipped from the factory with out a BIRD and without a Trik-L (because they hit the market in 2005 I think); and it is well document my coach, that a lot of RV were shipped without the ability for the alternator to charge the house batteries. And I solved this problem by adding the KeyLine VSR.

If you want to explore the Winnie website to look at my circuit diagram, here's my 2004 Itasca Horizon 40AD coach Serial#70S80E239720.

I'm not saying your wrong. I'm saying I still don't understand my RV solenoid connections based on your comments above. So I hope to confirm things with my multi-meter in a couple of weeks.

====

Next: Would you say the Trik-L is only useful when storing the RV... with shore power?

This thing seems useless to after you install the KeyLine VSR. And as noted above it's just another unreliable part that should never have been installed. Granted it was good enough to sell the coach, but Winnebago should have put in a better unit. (Maybe there were no better battery isolator type devices until 2010? Does anyone know when BlueSea or KeyLine hit the market?
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Old 04-14-2021, 08:29 PM   #7
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ashaffstall: If you still have your solenoid cover off, maybe you can tell us if your Boost Solenoid coil is always active (+12V)?

A) BDS-on, Key Off.

B) BDS-on, engine started.

This will help address the points we are talking about above.

Thanks.

PS
In order to get a maximum charge going to your house batteries you would want to measure this when the SOC is at 50% or about 11.9 - 12.0V.
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Old 04-14-2021, 08:48 PM   #8
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This may help some.

See attached diagram for Trik-L-Sart (TLS) and your diagram. In my coach the Trik-L-Start BLUE lead is attached to the "Always Hot" terminal of the Boost switch in your diagram and the YELLOW lead goes to 12volt RIGHT side terminal as pictured in your diagram.

When the salesman switch (relay) is ON and coach is connected to shore and charging the house batteries, voltage is siphoned via YELLOW to the TLS and from TLS to the "Always Hot" of the Boost switch. TLS is designed to flow current only from YELLOW to TLS to BLUE. Mine failed and when essentially allowed Bi-directional current flow as if I hard hardwired the Coach batteries to the Chassis batteries. It has worked flawlessly since I purchase the coach in 2013 and kept the chassis batteries topped off. That is until I was in Port Aransas TX and got caught in that awful winter Texas blackout.

I will get a photo of the installation.

Your are correct in that if there was some power drain in coach (e.g., left an exhaust fan on) and I was not on shore power then in a day or two all FIVE (2 chassis, 3 coach) batteries would be dead. Fortunately, I have had enough electrical issues with my coach that I keep and eye on every little anomaly.

I will be getting another TLS but I will likely put an inline diode one of the leads as insurance against a second occurence of same issue.
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Old 04-14-2021, 08:50 PM   #9
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I'll respond more fully later, but the Boost Solenoid isn't always on, only WHEN THE ENGINE IS RUNNING or the BOOST SWITCH IS DEPRESSED.
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Old 04-15-2021, 12:55 PM   #10
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Thank you both for the additional points.

I added a comment to the Trik-L-Start diagram below. If you find it to be in error, please let me know.

Can you confirm the Trik-L wires DO NOT connect to the coil side of either the BSD or the Boost Solenoid?

==> Some one should add a Boost Solenoid and BDS to the circuit diagram so we don't get confused.

cbeierl: How does my 2004 Itasca Horizon 40AD boost solenoid remain "hot" all the time?

I can't confirm were my "LR" wire to the boost solenoid is coming from? ...And I may have not drawn it properly in the circuit diagram above. TBD.

When I get to a camp spot for 2 weeks I will have time to measure everything with my voltmeter.

==> Remember, my coach never came with circuits that allow the alternator to charge the house batteries. And that's why I installed the KeyLine VSR (battery isolator.)

Speaking of the KeyLine VSR. I need to re-verify those charging numbers I posted above. I.e., I don't understand how I can have different current (amps) values flowing out of the VSR?
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Old 04-16-2021, 04:58 PM   #11
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KeyLine VSR Amps From the Alternator To A 12.0V House Battery Bank

I need to correct a previous effort to measure the amps of current in my two KeyLine VSR wires where one lead goes to the house batteries and the other lead goes to the engine batteries.

So, I added the KeyLine VSR (aka Battery Isolator) I did this because Winnebago shipped my RV without the capability for the alternator to charge my house batteries. And it has worked very well and has never failed me in 6 years. I highly recommend this over the Trik-L-Start or Amp-L-Start which is a one-way trickle charger.

My RV also has 400W of solar on the roof, and on a good sunny day I know it can put out 20-21 Amps to my house battery bank. ...And with the KeyLine VSR that will also keep my engine batteries "topped-off" when the engine is not running and the sun is out.

What I want to know was how many amps were being passed from the engine battery to the house battery -- with my engine running?

So today, after I awoke in the morning, and after boondocking for the night... I measured 12.0V (or ~50% SOC) on my 4-GC2-6V Golf Cart Batteries... and why did I start here?

Answer: I wanted to measure the current from my alternator to my house batteries when my house batteries were at their lowest -- so they would absorb the most current from the alternator. And this is what I measured:

A) Engine at 1000RPM (Cummins ISC-350)
Alternator rated at 160A, but probably only 50% efficient
400W of solar disconnected to the house battery bank...

==> The KeyLine VSR was allowing 14A to pass from the engine battery bank to the house battery bank.

...Now this is where it get a little more interesting.

B) Using the same configuration as outlined above, only this time my 400W of solar were biasing my house batteries, and this what I measured:

==> The KeyLine VSR was passing only 11V to the to the house battery bank vs. 14A without the solar panels working to produce a charge.

WHY?

* My guess is that the KeyLine VSR, which is a "bi-directional" relay, with cut-in and cut-out voltages, favor the weaker battery bank.

Meaning, current will flow to the weakest battery, because DC current can only flow in one direction, and it's always from a Higher Potential Voltage Source to a Lower source.

The voltmeter will not tell you which direction current if flowing, but since we know the house batteries were at 12.0 V and the alternator was outputting 13.7V, by virtue of the alternator supplying this voltage to the engine batteries, then we know current was flowing from the engine battery bank to the house battery bank.

...So why did the current drop by 3V with the solar panels working to also charge the house batteries?

Can someone explain that. Is it just simple circuit analysis? ...which I'm not that good at! ...Are there just not that many "holes" in the house battery plates (available to fill) with the solar charge controller putting out 15A on this day?

And with 15A going into the house batteries (21A max on a better sunny day) and with 11A going into the house battery bank from the alternator, I think that tells me 26A are being supplied to my house batteries.

If this is the case and at 12.0V when I start driving off in the morning to my next destination, the question then becomes: How long would I have to drive in order to fully charge my battery bank from 12.0V (~210AH) to 12.8V (420AH), which is 210Amps?

Answer 210A/26A = 8 hours.

And what about a sunny day when my solar controller is putting out 21A?

Answer: Total current equals 11A from the Alternator + 21A from my solar for a total of 32A. Therefore 210A/32A = 6.5 hours.

Note: This test was conducted with my Alternator at 1000RMP so I will need to repeat with my engine at 1500 RPM to see if the alternator outputs more amps -- in which cast the driving time listed above will be less. TBD.

Note: The above test may be accurate of flawed somewhat, because I have to make some assumptions, but I can say with certainty that I highly recommend the KeyLine VSR to all RVers; and when you have solar panels it is even more important to have the VSR so the engine battery gets charged when you are camping and using some of the 12V accessories (like your radio) when the engine is not running.
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Old 04-18-2021, 04:26 PM   #12
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On my Itasca Meridian 2004, the boost switch activates a solenoid / relay which bridges between the chassis and coach 12VDC systems. There is no B.I.R.D. system on my unit, and the factory confirmed that it was not installed on my serial number.

While the boost switch is momentary contact, the relay it activates is rated for continuous duty. I use a tie-wrap jammed under the switch to emulate what happens when the engine alternator is running. If on shore power the chassis batteries are bridged to the coach batteries, and are then effectively charged by the Dimensions charger.

The same can be done when running the generator, and that will allow the chassis batteries to also get charged while running the generator.
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Old 04-18-2021, 05:16 PM   #13
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I think all the the 2003 thru April-2004 Winnebago Class A's did not come with a BIRD or Trik-L-Start. And I'm glad for that.

Also, I get that the boost solenoid is "not" on all the time, so I stand corrected. I meant "on" all the time when the BDS is on all the time.

So I'm looking to clarify "When does the Boost Solenoid turn on?" ...And is it different for us 2003 to early 2004 Class A Winnie owners?

Monobird seems to have come up with his own "work around" to charging the house batteries off the alternator. And since this is a direct-parallel-connection, I wonder how many amps the alternator is sending to the house battery bank when the house bank is at 40-50% SOC (11.9V-12.0V)... and the engine batteries are fully charged or close to it?

My guess is that the battery's internal resistance limits the amount of current, and it never gets so low that the alternator gets overloaded. This is one advantage of FLW deep cycle batteries vs. Lithium LiFeO4 type batteries.

So as the battery SOC climbs the internal resistance increases, and the charging current decreases. It's virtually it's own voltage regulator.

I also have learned this Trombetta boost solenoid used to burn up their coils rather quickly, but then I found out Trombetta changed the design to handle 15A sometime in the 2010-2012 era (I think). So it's questionable if you need to do the following, but if you want your Trombetta Boost Solenoid to last a life time then you might want to follow this tip by Cbeierl:

Cbeierl says he prolonged the life of his Boost Solenoid by wiring a couple 1-ohm, 10W resistors in series with the coil power wire to lower the voltage by -2V. (See picture below.) ...So, when I get to my camp spot in a couple weeks, I'm going to look into this option myself.

First, I need to verify if my Boost Solenoid is "on" all the time; and if this is in the case, of which I have my doubts for my 2004 Itasca Horizon, because Winnie did not wire my coach for the house batteries to charge off the alternator, and I'm glad that this the case, because I trust my KeyLine VSR to perform that function better and more reliably. And this VSR also handles my solar controller output too when my house batteries need to pass current (amps) to my chassis-engine-battery bank.

I also plan on adding a reverse biased diode between the coil "+" and "-" posts... which will safeguard the momentary boost switch mounted in my dash from frying it's contacts due to "fly back" spikes.

...And while I have my solenoid box cover off, I will add another reverse bias diode to my BDS coil terminals too. Note: The BDS switch is not subject to the same high levels of "fly back," but it sounds like a good idea to do anyway; and the cost of these diodes are about $1 each or less.

These diodes need to be of the high voltage variety, but because there is so little amps going thru them, they will not put any significant drain on your batteries when you are boon docking. (Think in terms of Amp-Hours (AH) and this will be easier to accept.

I.e., there is no current though the coil when the trigger switch (to ground) is off.

Is this overkill? ...Maybe, but it's a cheap upgrade and for me it was part of the learning process.
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Old 04-18-2021, 06:04 PM   #14
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Quote:
Originally Posted by imnprsd View Post
...

Monobird seems to have come up with his own "work around" to charging the house batteries off the alternator. And since this is a direct-parallel-connection, I wonder how many amps the alternator is sending to the house battery bank when the house bank is at 40-50% SOC (11.9V-12.0V)... and the engine batteries are fully charged or close to it?

...
There is no workaround for charging the house batteries. They will always charge with the chassis alternator (via the "boost" solenoid/relay).

The workaround I have is to charge the chassis batteries when on shore power or generator power, by locking in the momentary boost switch.

I agree with a suppression diode, but it need not have a PIV of 800V. A 1N5404 would likely do the job if it is easier to find. The 1N5407 diodes are cheap so if one has to be ordered, go for the -07 which is an 800 PIV diode. It's overkill at $0.08.

I posted what I did because I have a Itasca Meridian 34H which is probably quite similar to the Journey the OP has.

OP should consider calling the factory to set straight his understand of what his system is like.

My hunt to nail down my 12VDC system started when I found dead batteries one day and discovered that there are at least 3 paths (normally) for the house batteries to supply power to stuff. And I was under the misimpression like him, that throwing that switch would kill power to most everything on the house batteries.


To answer the current flow musing...if the chassis were fully charged, and the house was at a low SOC, I would expect a high current flow, not only from the alternator but also from the chassis batteries, bringing them down a little from a full charge. For that reason and others, I would prefer that each of my battery banks charging be done b a smart charger, configured for the batteries in use. But that is another topic, and can be pursued later.
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Old 04-18-2021, 07:09 PM   #15
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MongoBird: Sorry for misspelling your call sign in the previous post; and for the clarification.

I sometimes try to stitch comments together in a summary so the thread topic can reach a conclusion; and I sometimes miss the literal translation(s).

You know about diodes than I do, I can tell.

When I finish making these upgrades I will post another thread.

The part about current musing is interesting, because I have very successfully been using a KeyLine VSR (aka battery isolator) to join my house battery bank to my engine battery bank.

This VSR is my cut-in and cut-out safety switch.

So thank you very much for clarifying your "work around" is used when you park your RV with a charging source and you do not use it when you are driving.

Charging Update -- When You Find Your House Batteries at 11.8V:

* Last night I camped overnight in a Flying-J and in the morning I woke-up with my cube heater running on low. My house batteries were at 11.8V.

* I started my generator and my solar was putting out 5A at 7AM.

* I put a camp on the Battery Cable (To/From) my Dimensions Inverter-Charger after I selected 20Amps of charging current on my selector panel... which showed up as 90A on my charging display... and this what I got:

==> The charger was pumping 77A to the batteries.

That means ~13A is lost somewhere. Any ideas? ...For example... I know I have a long battery cable (~6' long) since the inverter is on the driver's side of the RV and my house battery bank is on the passenger side.

Note: The KeyLine VSR cables that join my house batteries to my engine batteries were reading ~ 2Amps, suggesting my engine batteries were full. So, I guess there is nothing special about this.

However, MongoBird, if you used your "work around" knowing that an empty house battery bank will suck-up 77A+ (in my case), wouldn't your work around pull a lot of current through the boost solenoid... and out of your engine battery if it remained "hard wired" for very long? ...And you DID NOT have a charger running?

I think these batteries act like a "sponges" when they are low and will pull current for a number of Amp-hours until they get to above 80% SOC. What is your experience on this subject if you care to muse a bit more? I'm interested.

...Or maybe you would only jam your Boost Switch "closed" when you have your House SOC above 80%?

...I guess I'm asking if there is any downside to your workaround, which is a good idea, I think, but maybe there are some caveats? ...Like maybe you should only use this "jam-up-switch" when you have a charging source and your SOC is above 80%? ...Or you can suggest other numbers.

Thanks for sharing your electrical experience.

PS
What is the downside to using a higher PIV diode in both the Boost? ...And would you recommend against the higher PIV for the BDS, because it is on all the time?
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Old 04-19-2021, 08:32 AM   #16
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No downside to using a higher PIV diode, except cost and availability, which with a $0.08 cost means only availability.

With respect to bridging one battery bank to another with disparate charges, there are some risks and wear concerns. Those concerns also exist for using the propulsion alternator to charge batteries.

Essentially, low rates of charge are desired for AGM, FLA and GEL type batteries. Personally, I like 10amps or less. So ideally, if I arrive at a shore power site, and will spend the night, and be connected for 10 hours, then I would like to restore a charge over 10 hours, not the first few hours. This is why I would rather have a smart charger for both house and chassis batteries. (However I have not implemented that as of yet.)

With respect to current flow in the contactor/relay/solenoid, I believe it is rated for expected currents. At least in my case, the alternator is rated at 160 amp output, and is fully capable of that.

With respect to missing amps, keep in mind that an alternator is only a power supply. It is not an ideal battery charger. Just a power supply. So as battery impedances change, the current flows will change. A smart charger could better manage the charge profile.

Battery impedance and acceptance of charge information is readily available. If you imagine percent charge like the leading edge of a sine wave, with a constant voltage source, that will be a close approximation.

We haven't discussed it here, but smart chargers can also employ desulfation strategies and waveforms, which are very helpful, and are ideal for longer term storage situations. Unfortunately they are most effective in warmer temperatures, and most of us store batteries in colder temperatures. In my experience I have seen better battery life with desulfation methods than without. Also smart chargers differentiate between FLA and AGM batteries, some better than others, and being able to tailor a charge profile to the chemistry is another optimization.

As for when to jam the boost switch...I would consider it whenever there is shore or generator power, and the chassis batteries are also low. Give the chassis batteries some love. I would also consider topping off the chassis batteries for an hour before a cold weather start. Along that line, when starting the propulsion engine, and it is cold out, I would use the boost switch to provide a little more power at the time of engine start to keep the voltage higher and share some current draw for starting. Most deep cycle AGM batteries are not really rated for cold starting large engines, but they will help, and having both banks of batteries near full charge will also help.
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Old 04-19-2021, 10:22 AM   #17
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Excellent comments! I appreciate it and learned some things.

Among them is using the boost switch to help start my Cummins ISC-350 in colder climates (sub 40F I'm thinking) to assist my engine battery's cranking ability, since both batteries will be suffering some cranking amp losses in the cold.

Another good point you made talks about desolation and the need to "boil-off" the sulfate accumulation on those cell plates (using high voltage); as needed and for the right length of time; and only smart and smarter chargers can do this... better and then a so called dumb-charger.

And for those who always charge there batteries at the highest charger setting, which shows a "charger draw" of 25A in my case... and that delivers up to 100A to the battery; then you will end up replacing their battery bank sooner vs. charging them at 10A for a longer period of time.

MongoBird: I have one last battery question I can use your advice on: Does adding 4oz of mineral oil to each battery cell... help reduce or prevent water from evaporating out of the cell? ...And is there any downside?


3 cells per 6V battery x 4 batteries is 12 cells total. So you will need 48oz (12x4=48) for all 4 golf cart batteries.
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Old 04-19-2021, 11:09 AM   #18
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I would not add any mineral oil to a lead chemistry battery. It won't change the "boil-off" which is mostly hydrolysis due to imperfect charging and/or overcharging.

Distilled water is the time honored additive.
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