System can't keep up after upgrades and reconfiguration

[Wellbuilt]

A fellow boondocker (w/ several years experience RV-ing, internationally) gives his batteries a boost by connecting a charger to his car battery on one end and his battery bank on the other, then idling the car for a couple of hours. I'm having trouble finding a device like this.

This dosent really help much car alts don’t really have the guts to charge like that , really you need yo get a really inverter / charger and all your battery problems go away .
There is no way around this .
With only solar charging your system bad weather will just walk your battery down to nothing
MOST RV res are in way over there heads with this stuff .

 

[Wellbuilt]

it's not, really. We retired early in large part due to frugalness. Hard to turn it off once you get here, though...

O cool the I would drop a few bucks on a proper off grid inverter and make your problems go away

 

[time2roll]

A fellow boondocker (w/ several years experience RV-ing, internationally) gives his batteries a boost by connecting a charger to his car battery on one end and his battery bank on the other, then idling the car for a couple of hours. I'm having trouble finding a device like this.

That would be a DC-DC charger. Victron and others have these. They will charge mismatched voltages too. If it is all 12v lead-acid just connect direct with your jump cables.

 

[dixonge]

A fellow boondocker (w/ several years experience RV-ing, internationally) gives his batteries a boost by connecting a charger to his car battery on one end and his battery bank on the other, then idling the car for a couple of hours. I'm having trouble finding a device like this.

ok, never mind on this - I misunderstood what he was talking about. In any case, not an option that would work on our rig.

 

[dixonge]

My friend recommended one of these - can plug into the rig using any AC outlet and then power with generator, or can plug it into an RV park power pedestal. Comes with all the options needed to properly charge deep cycle. Would mount it in the battery compartment and leave it connected to the battery bank.

Sterling ProCharge Ultra 40 Amp Boat Battery Charger

The Sterling ProCharge Ultra 1240 marine battery charger is an award-winning, ocean-proven, intelligent charger with a 5-year USA warranty

baymarinesupply.com

 

[dixonge]

Filling them to the slot is perfect ,? you may not have enough power to mix the electrolyte .
Are the battery’s fizzing when you are charging ?
Do they get a little warm .

they fizzed better when doing only 2 at a time. Unsure if warm.

 

[Wellbuilt]

Fizz is good , they should be a little warn allso I shoot mine with a heat gun .
You should probably feel around the sides, top wires terminals .
My battery’s go up 5o from the morning 2 the end of charging .

 

[dixonge]

maybe something like this?

https://www.amazon.com/PowerMax-PM4-100A-Converter-Battery/dp/B01ER3LH3O/ref=as_li_ss_tl?th=1&linkCode=ll1&tag=vc-electrical-20&linkId=d8548aa852a41b8ce022d573b5e907c1&language=en_US

 

[Wellbuilt]

My friend recommended one of these - can plug into the rig using any AC outlet and then power with generator, or can plug it into an RV park power pedestal. Comes with all the options needed to properly charge deep cycle. Would mount it in the battery compartment and leave it connected to the battery bank.

Sterling ProCharge Ultra 40 Amp Boat Battery Charger

The Sterling ProCharge Ultra 1240 marine battery charger is an award-winning, ocean-proven, intelligent charger with a 5-year USA warranty

baymarinesupply.com

That look like a good charger .
but I would up grade to a inverter charger and be done with it .
Just sell your inverter in camp to some one .
This is a good unit it will work seamlessly it’s a few bucks more

 

[Wellbuilt]

If you get a charger make sure its power factor is corrected the genarator will thank you

 

[dixonge]

That look like a good charger .
but I would up grade to a inverter charger and be done with it .
Just sell your inverter in camp to some one .
This is a good unit it will work seamlessly it’s a few bucks more

I'm leaning toward a charger-only solution. When using the charger with the generator or a park pedestal I would turn off the inverter and the SCC, just to isolate things and remove battery load.

If I had an inverter/charger, I could theoretically end up with the following power path:

* Generator > inverter/charger > shore power cable > internal transfer switch

If the transfer switch defaulted to the shore power cable wouldn't this create a loop? If it switched to shore power, the generator would no longer send AC to the panel and the outlet that the inverter/charger is connected to. I can see it getting very confused and switching back and forth a lot.

Of course if it defaults to the generator then all is well. But the inverter would be unused at this point, so might as well turn it off.

 

[Wellbuilt]

I guess the loop thing could happen , or your rig could get hit by a meteor ?‍

With the charger you could power loads and charge at the same time , you just don’t want to eq when the system has A load it will drop the voltage .

What happens with the inverter / charger is you power the inverter with the generator the inverter powers your loads and charges the battery
if you want to add Shore power you put a transfer switch between the generator and shore power .
My out back has generator in put and grid input ,I have no grid so I use my 2800 watt Honda on grid input and the 5500 watt generator hooked to generator input .
I start the generator and flip the switch and it works .
your coach must have the transfer switch between the generator and shore power all ready .
I would think if you wired the inverter to a outlet in the coach or the AC Circuit panel you could switch between generator and shore power normally
when You plug in the charger to shore power it will charge or float the battery’s automatically
you should have a converter to power the house bank .
How do you switch from generator to shore power ?

 

[dixonge]

I guess the loop thing could happen , or your rig could get hit by a meteor ?‍

With the charger you could power loads and charge at the same time , you just don’t want to eq when the system has A load it will drop the voltage .

What happens with the inverter / charger is you power the inverter with the generator the inverter powers your loads and charges the battery
if you want to add Shore power you put a transfer switch between the generator and shore power .

But my power path is battery bank > Inverter > shore power cable > breakers - that's how I power the house system.

The factory electrical system has both the generator and the shore power cable ending at the automatic transfer switch.

your coach must have the transfer switch between the generator and shore power all ready .

yep!

I would think if you wired the inverter to a outlet in the coach or the AC Circuit panel you could switch between generator and shore power normally

I made the decision early on to *not* attempt wiring the inverter to the AC panel. Reasons are: 1-extremely tight space, 2-Not an electrician

How do you switch from generator to shore power ?

If I have actual shore power, the transfer switch decides.

 

[dixonge]

Now leaning toward this unit + the extra module for 'smart' charging - all for under $150!

Iota Engineering DLS-55-X Regulated 55 Amp 12VDC Power Supply & Battery Charger

Note: Iota has discontinued this product.

www.solar-electric.com

 

[Wellbuilt]

Hmmmmm do you have a power converter to charge the original battery’s ?

 

[dixonge]

Hmmmmm do you have a power converter to charge the original battery’s ?

Yes, WFCO 8955PEC - it has 3-stage charging...

 

[Wellbuilt]

Hmmm so you are charging thru your shore power. Line into your converter to power the system ?


The iota makes a good charger but they have poor power factor .
the difference is with the iota charger you will need a 3500 watt generator to run it
the pro charger with correctEd power factor will use less then a 1000 watts
witch saves alot on fuel and wear and tear .
How large is the on board generator ?

If I have actual shore power, the transfer switch decides.

So you unplug the inverter and plug in the shore power cord to the power pedestal?

 

[dixonge]

Hmmm so you are charging thru your shore power. Line into your converter to power the system ?

when plugged into shore power, it charges the two hybrid house batteries using the normal RV WFCO converter.

The iota makes a good charger but they have poor power factor .
the difference is with the iota charger you will need a 3500 watt generator to run it
the pro charger with correctEd power factor will use less then a 1000 watts
witch saves alot on fuel and wear and tear .
How large is the on board generator ?

Onan 4000 (watts)

So you unplug the inverter and plug in the shore power cord to the power pedestal?

When in an RV park, yes, remove the shore power cable from the inverter and plug into a pedestal. The last time we used shore power was June 5th.

 

[dixonge]

The iota makes a good charger but they have poor power factor .

Two questions for you:

1 - Would this be an issue for my usage? I plan on running the generator 2 hours max maybe once every 7-10 days.
2 - If it is a problem that is so bad it is unusable, then what charger would you recommend with a better power factor? Keep in mind I'd prefer a simple charger, not an inverter/charger/mppt/kitchen-sink unit...

 

[Hedges]

Here's a nutty thought ...

Since your battery bank is four 6V FLA, wired 2s2p,
What if you disconnected two, ran inverter with just two batteries connected 2s (12V). In the mean time, charge and equalize the other two connected 2s. It takes a number of hours to fully charge and equalize. Once equalized, cells should stay that way for quite some time and battery regains capacity lost from differing SoC.

Couple of ways to charge:
1) AC powered charger, plugged into the inverter and charging the other two batteries (while the sun shines.) Yes this may draw down the batteries on inverter, but what it could accomplish is fully charging the other two and bringing their cells to same SoC.
2) Disconnect SCC from system, (so inverter is running off batteries without SCC as if sun has gone down.) Use SCC to charge & equalize the other two batteries with no load connected.

Of course #1 requires a suitable charger. But 100% of PV/SCC power harvesting gets used. #2 may waste available PV if the batteries being equalized don't accept all available power.

If doing equalization with the two disconnected batteries physically sitting in the same place, keep compartment lid open. Maybe lay a sheet of cardboard as baffle to deflect outgassing out of the compartment.

After charging/equalizing your four batteries two at a time, one pair will probably have been drained back down lower than the other. Connect the fully charged set to inverter and operate with them until voltage same as other pair before paralleling.

Lead-acid needs to be fully recharged on a frequent basis, so whatever PV is available, minus inverter inefficiency and battery round-trip losses, is all the power you have available. Consumption needs to be low enough to get batteries back to full charge.