Not Getting Full Charge With Marinco Shore Charger

Steve and Karen

Steve and Karen

Ranger
I have recently installed a Renogy DC-DC charger and a Victron SmartShunt and have been playing with both, getting used to their apps and idiosyncrasies. And they're both working great. Or at least, exactly as I expected.

However, the shunt readings have provided me with some data that bring the behaviour of my factory Marinco shore charger into question, and whether or not it's the right device for the job.

I took out 11Ah (using the lights and fan, at a constant 2.0A draw for nearly 6 hours) and brought the SOC down to 88%. All of which added up. This is exactly 1/4 of my available amp hours from my 85 Ah battery that I can use. Not an insignificant amount. At this point I expected to be able to simply plug in the shore power and have it immediately start topping it off again. It didn't. The Marinco went into Absorption (red and green light) for 2 seconds and then switched to Float with no amps going in. I tried it an hour later. No go. Is this what I can expect from the Marinco? None of this would have been apparent to me up to this point, without the shunt data. The DC-DC alternator charger seems to have no problem recognizing that the battery isn't yet full at this stage, and kicks in charging at full regular absorption amp and volt rates.

The Marinco has a pre-set Absorption voltage of 14.3, which is considerably less than my AGM battery's recommended voltage of 14.7 (which shoots up to 15.0V when it's 50F). So maybe I'm not getting as quick a charge as I could from it, even if it was doing what it should.

A further concern, is that failing to fully recharge before taking out any amps would seem to be breaking one of the rules of thumb for ensuring longer battery life, and to not inadvertently and permanently reduce the battery's Ah "ceiling".

I suspect that detected surface charge voltages in the neighbourhood of 13.1V may be hindering the Marinco from recognizing the battery's true voltage, and from starting a new charge cycle. I could be very wrong about this as well. But it didn't stop the Renogy DC-DC from seeing that it was only at 90%, and less than the 14.4V the battery needs to reach for a full charge, and doing a correct top-off. So why would a shore charger get fooled?

Has anyone put one of these Smart Victrons in as a replacement for the factory shore charger?

Blue Smart IP22 Charger - Victron Energy

... and if so, would it be able to go straight to work, topping off a 90% battery, without needing a kick in the pants, or having to wait until surface charges dissipate to acceptable level, if ever?

If anyone uses another shore charger that seems to go to right to work, even when the battery is close to full charge, I'm all ears.

Thanks,

Steve
 
I have been using two other Victron chargers from the BlueSmart series for a few years now, one on the TD battery (100ah AGM Victron), and one on my pony battery (now a LiFePo4 50ah).

I am (newly) running a smartshunt knockoff on the TD batt, but haven’t replicated your test. What I can say is that both of my chargers are programmable with Victron’s app on my phone to match my batt’s best profiles.

edit
PS programmability goes beyond what Victron’s spec sheet indicates; I can set totally custom parameters in addition to the profiles available as presets.
 
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Thanks Seth.

The Victron I linked does have the ability to custom-set it to my AGM's 14.7 optimal charging voltage, at 77F but not any higher, for colder tempoeratures. But which is definitely a start.

My bigger concern would be being assured that a shore charger will top off my battery, rather than let it sit there at 85%-95%, happily doing nothing.

Methinks that anyone without an accurate shunt measurement (absolutely full battery followed by an accurate measurement of a known Ah drawdown) could easily be misled that their shore charger's inactivity in conjunction with an observable OCV of 12.8 means they are the happy owner of an absolutely full battery. When in reality, they're far from it.

I have yet to determine (from my preliminary on-line sleuthing) if the BlueSmart's advertised "6-stage charging algorithms" can accurately detect a "nearly full" battery and properly finish the job. It may be worth the gamble. If only to get the guaranteed higher Absorption rate that Fullriver recommends.
 
Update:

I got a spare Marinco/Guest from Cary back in the fall in anticipation that the OEM would go bad at some point. As a test, I plugged it in and it immediately went to work. Whereas the OEM went into Absorp for 2 seconds with 10A, and then immediately went to sleep. The OEM is getting replaced. But possibly not by its twin.

If my charger is going to go bad, I'd rather have it go bad in this direction, than by way of runaway charging and a fried battery or trailer.

I have a Victron IP67 7Amp coming. Slightly larger, can't go in the same place as the Marinco and will require some bin modifications. However, it is fully BT-enabled, like my shunt. And can be programmed specifically to my AGM's unique Absorp and Float voltage specs, which the Marinco couldn't do, and which was significantly on the conservative side of the charge spectrum. Which it should be, for a do-all, all-battery-type charger.

Will post the Victron's mounting when it goes in, possibly on the bin divider side of things, and my OEM hole cover-up solution. Whatever that may end up being.
 
Steve and Karen said:
Thanks Seth.

The Victron I linked does have the ability to custom-set it to my AGM's 14.7 optimal charging voltage, at 77F but not any higher, for colder tempoeratures. But which is definitely a start.

My bigger concern would be being assured that a shore charger will top off my battery, rather than let it sit there at 85%-95%, happily doing nothing.

Methinks that anyone without an accurate shunt measurement (absolutely full battery followed by an accurate measurement of a known Ah drawdown) could easily be misled that their shore charger's inactivity in conjunction with an observable OCV of 12.8 means they are the happy owner of an absolutely full battery. When in reality, they're far from it.

I have yet to determine (from my preliminary on-line sleuthing) if the BlueSmart's advertised "6-stage charging algorithms" can accurately detect a "nearly full" battery and properly finish the job. It may be worth the gamble. If only to get the guaranteed higher Absorption rate that Fullriver recommends.
Click to expand...

Very helpful explanation. Caveat: I'm a high power user so what I am doing is probably overkill for most. My goal is as much POWAH as possible within reason in the CI. I had my 2010 backfitted with solar roof, and the CTEK to run it and the alternator charging, bith that have worked brilliantly.

I have tested out a Noco5 as replacement for the old Marinco which Cary said does have a failure mode of overcharging on the older models. (And probly did on mine but also my bad for not checking the flooded cell (i mistakenly thought the new battery was an AGM, and also I used it on a long trip in very high ambient temps- so its probably part that too.), lesson learned!

I'm installing the Victron Shunt and 15 17 charger (for the higher charging rate) to go with the Precision LiON battery. My 2010 predates the red DC shutoff switch so my battery cover door has a bit more room and the charger will go there, next to the AutoW. The CTEK is on the aft vertical surface of right galley, so I just store soft stuff on that side.

I look forward to checking the actual draw of various items in use so I can make better informed decisions on "how much how long/which to turn off when"; dometic, laptop, iphone/ipad, fantastic fan, furnace, based on actual numbers, vs rough guess so far. Plus pull the fuse on the AutoW as needed when parked off power long term.

If I put the money towards a bigger deep cycle lead acid like your Fallriver or the Victron Seth has used, then this info is even more useful, to get max bang for buck on the lead acid where the last stage of charging to 100% or repair is highly dependent on the specs of the charger.

Someone using relatively low/minimal power on the OEM lead acid battery is probably fine,
without,
or better-
should order the TriMetric with the readout. And Necedah having figured all this out already.

My guess is that covers 80-90% of CI owners, or buyers of used.

Steve, Seth: Has Victron tech support been helpful?
Any other RV websites with more early adopters sharing same?

Appreciate the help!

PS: fyi the Victron Connect app works well on iphone and the BT range is sufficient standing next to galley, hatch up- like if I were standing there looking at the TriMetric.
With galley Hatch closed, and shunt inside battery compartment; not so well.

I'm checking next how well I can read the Victron app and range if inside the cabin, on a rainy day- thats all through wood so I'm guessing better, and I'm guessing the aluminum skin and stainless steel galley layers are the biggest impact on BT range which is a combination of the device inside victron charger and shunt, and the BT device in phone. I'll try it on ipad mini, too.
 

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Kevin S said:
Steve, Seth: Has Victron tech support been helpful?
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Haven't needed them yet with just the shunt connected. Will see when I get the IP76 charger. But the On-line info and manual and fairly intuitive .

Kevin S said:
With galley Hatch closed, and shunt inside battery compartment; not so well.
Click to expand...

Similar experience. But far from a deal-breaker.

In communication with Necedah today, my Marinco failure (it couldn't to go to Absorp at the upper end of re-charging and be able to top off the battery) has not been a common failure of the OEM charger. But like I suggested, without a shunt, and knowing how many Ah I had taken out, (and having the behaviours of two other chargers to compare it with) this scenario could have gone on for some time unbeknownst to me, and shortened the battery's life. Further, it would have been very difficult to diagnose. Without, perhaps, killing a bunch of batteries in the meantime. Voltage can only tell you so much.
 
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Kevin: I should add that I don't plan on using the shunt to its fullest designed capacity: just counting Ah out, followed by recharging to a known "full" by watching what each of my chargers do, and then doing a manual reset every time.

Much of the many VictronConnect app's user-defined settings are required to be set, to get it to crunch the numbers for the Auto-Sync back to 100%, which I don't intend to allow it to do.

So other than adjusting for age, temp, Peukert, and efficiency, on a very intermittent schedule, I will only be plugging in Absorp and Float voltages, and shutting down any EQ, as my AGM will not like an EQ.

So I may not be the best person for any LiON-related questions you may have.
 
Thanks Steve. I got more reading to do it seems.

As you pointed out lots of the fine tuning is not needed on lion. Just actual State of Charge and some advance notice when that drops off steeply.

I'll share any tips but wont be diving nearly as deep as you and Seth, and my guess is Cary will have more insight as more CI owners check in with lion installs and corporate memory expands on how long things last using x,y,z.

PS: I only call him when I've already RTFM and still have totally confuseled myself, in spite of...;)
 
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Kevin S said:
…I look forward to checking the actual draw of various items in use so I can make better informed decisions on "how much how long/which to turn off when"…
…Steve, Seth: Has Victron tech support been helpful?
Any other RV websites with more early adopters sharing same?…
Click to expand...
The shunt is fantastic for real analysis! I was able to do some really quick figures on draw of my various loads, including CPAP, best AND most accessible info I’ve ever gotten!

Like Steve, I’ve not needed to contact Victron support. Early on I did have an enlightening conversation with a marine Victron dealer/installer at pkys.com, prior to purchasing my big AGM.

The shunt and the CTEK 12v charger both seem really valuable. After years of futzing with various installs I feel on top of it…

Victron’s website includes more than product info, see various calculators here:
Software - Victron Energy

And, more than you want to know about power storage here:
https://www.victronenergy.com/upload/documents/Book-Energy-Unlimited-EN.pdf
That white paper predates lithium, but still chock full of relevant info.
 
Seth is right, the shunt is great for analysis and review, especially since it can give a historical review of amps used and voltage of the battery. This problem is not caused by the shunt, it appears it has just made it visible. Likely we've all been running around with a partially depleted battery for some time, though maybe not.

The problem statement for the 10 amp charger, in my case the noco 10 amp:

The NOCO 10 amp charger, when charging a battery (AGM) reaches its float output prior to 100% charge. If the draw from onboard electronics is higher than the Ah output (Amp Hour) output of the charger, the battery never achieves a full charge. The NOCO does not revert back to bulk charge, eventually resulting in a false report that the battery is defective and charching will cease.

If the NOCO is resetarted, bulk load will resume at the higher amperage output, possibly resulign in a 100% charge. This charge will be maintained unless the Ah usage of the camper exceeds the Ah output over time of the charger while in 'float' mode.

The NOCO will not automatically revert back to bulk charging, making the restart necessary.

Does this make sense? Is this, in summary, the same behavior other chargers are seeing as well?
 
Sweeney said:
Does this make sense? Is this, in summary, the same behavior other chargers are seeing as well?
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It does, and ...quite likely. This is why I likely won't be placing too much credence in the shunt to do an accurate assessment of amps going back in, or leaving the decision up to the shunt to do a 100% re-set. I think it's easy enough after a couple sessions for me to lift the lid or open my phone and see when it has conclusively reached full charge parameters for my particular battery. And do the manual reset. Then you know you're back at square one. I trust the shunt to keep a good eye on Ah used and when to "turn around". Or to give a good history, or a snapshot of in-the-moment usage that can be extrapolated. Which is where, I think, it be most useful.

Sweeney said:
Likely we've all been running around with a partially depleted battery for some time, though maybe not.
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This is certainly the impression and conclusion I've been left with. Probably a miracle I got years out of the OEM battery.

The more I discover about the pitfalls (and continuing expense) of a dedicated, installed trailer battery, and all the fixes and add-ons required to allow you to use it properly, charge it properly and not prematurely kill it, the more I wish I had left the battery compartment empty, and explored using a larger portable Lithium (or even a large and a small), connecting it to the trailer via the 12V socket on the side or inside, if and when I need to run anything 12V. A small one could easily take care of the fan, lights and pump. And a larger Li for the Dometic. In another lifetime, I suppose.
 
Sweeney said:
he NOCO will not automatically revert back to bulk charging, making the restart necessary.
Click to expand...

I don't have the Noco. But any time you are charging and drawing simultaneously is, I think, a ripe opportunity to confuse the heck out of these things.

It's nearly impossible to do uninterrupted recharges (where you aren't pulling some charge for a device at some point). But I think that has to be ideal to shoot for. A road charge with a DC-DC should be long enough duration to get you back to 100. Solar is always a crap-shoot. And shore power charging will nearly always be interrupted by a draw-down. Unless you save your charging till bed-time. Even then...

Look at this way... if you pored over Seth's Victron link above, and all the power considerations required for mariners, I think our list of charge and use considerations and concerns for a single-batter trailer is fairly short.
 
That's part of the reason I didn't go with LiFePo in the TD. Pretty expensive to have dedicated to that use alone with as much camping as we are normally doing, where as the Sogen can be used for the Dometic as well as back up power for the TD. When not camping it can be back up power for the house during a storm if needed for a few hours, and I've gradually been replacing some of my gas powered tools with electric as needed, and using the sogen to power those as well, like a leaf blower for our 1/4 mile long driveway when the gas one died, and pole saw to use along the same stretch. I just throw it into the little trailer behind the Rokon along with a 100 ft cord and make my way down and back. Like most things, it's a compromise of some sort, but works for me at this stage of life.
 
I installed this charger under number 701 to replace the OEM charger. Note that it had to be installed forward of the water tanks in order to fit as it is larger than the OEM charger. https://a.co/d/9TappHV
I don’t have of the detailed data that you are looking for but as far as I can tell it works great. As someone pointed out, you can program your charging profiles.

For me, the key to power management has been t9 dedicate a SoGen to my refrigerator and take that load off the trailer battery. I keep the fridge in the back of my truck and my SoGen charges while driving via a DC to DC charger on my truck and auxiliary line that runs back to the bed. I am EXTREMELY happy with the Goal Zero Yeti Core 1000. https://a.co/d/9ORIgGI I especially like the solid connection to my auxiliary charging line and fridge via an Anderson Powerpole plugs. I previously had a Jackery which only had cigarette lighter plugs. I could never get them to maintain a solid connection even when not driving.

Last weekend I camped three nights in the desert with 90 degree plus temps and the fridge plugged into the Goal Zero. The Goal Zero never got below an 80% charge and after a 30 minute drive, was backup to 100%. For longer trips I can top off with a solar panel.

Randy
 
dustinp said:
That's part of the reason I didn't go with LiFePo in the TD. Pretty expensive to have dedicated to that use alone with as much camping as we are normally doing, where as the Sogen can be used for the Dometic as well as back up power for the TD. When not camping it can be back up power for the house during a storm if needed for a few hours, and I've gradually been replacing some of my gas powered tools with electric as needed, and using the sogen to power those as well, like a leaf blower for our 1/4 mile long driveway when the gas one died, and pole saw to use along the same stretch. I just throw it into the little trailer behind the Rokon along with a 100 ft cord and make my way down and back. Like most things, it's a compromise of some sort, but works for me at this stage of life.
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Makes sense. I do same as my pony battery is a sogen- a backup to run a cpap, rechargeable by solar.

Since these things are getting improved every generation, imho its Lots easier to just get a new sogen in five years than a whole lion battery and all the gear to make it work, when a flooded cell or AGM lead acid is perfectly good for most CI typical weekend camping or longer in a park with power.
 
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