Battery Charging from shore power

[Jason687]

Have recently acquired a 2011 Montana 3150RL. No solar on rig. Need to replace a dead battery. First thought is to understand the charging system when connected to shore power. From the factory, did this rig use a multi stage charger that includes trickle charging once a full charge is reached, or will I burn out the battery if I leave shore power connected during winter storage?



Are there any useful after market upgrades other owners have made to the charging system to improve effectiveness?


Thanks in advance for comments/help in understanding.

[WeBeFulltime]

Your unit's converter should have multi-stage charging and would not overcharge and damage battery provided the factory converter has not been replaced with an inferior one. We full-timed for 10 years always plugged in and never a problem with our 2008, 2012, and 2018 Montanas.

[DQDick]

Same for us. Fulltime for 12 years now and always plugged in.

[Rondo]

Jason- How many batteries do you have in your unit? If you have more than one you should change out all of the batteries instead of just the single bad one. If you only have one battery you will be fine but I suggest you think about putting in at least two batteriesl A unit can chew up a single battery with no problem at all. If you have two batteries and replace only one of them, the new battery will loose power or charge because the older battery will bleed power from the new battery to equallize the power each have.

[Jason687]

Thanks for all the helpful advice. Some further info...
My rig came with a single group 24 deep cycle marine battery. Looks like the box could accommodate a group 27. I'm considering replacing with a UB1210000 AGM 12V battery (or possibly two of them).

I did install two 6V batteries in our last 5th wheel (and upgraded the charger to a 4 stage smart charger) but, over 17 years we have not actually boondocked... so I'm a bit uncertain about needing the added capacity of 2 batteries.
I guess I'll have to open up the electric panel to see what is in there and then figure out if it may or may not be appropriate for charging an AGM battery.

[DutchmenSport]

1 pop-up, 3 travel trailers, 1 fifth wheel, all of them plugged in 24x7x365 at home and camping, all year round (25 years worth). The only them they were not plugged in is when actually traveling on the road. Never had a problem with any battery.

[432bartman]

Originally Posted by Jason687

Thanks for all the helpful advice. Some further info...
My rig came with a single group 24 deep cycle marine battery. Looks like the box could accommodate a group 27. I'm considering replacing with a UB1210000 AGM 12V battery (or possibly two of them).

I did install two 6V batteries in our last 5th wheel (and upgraded the charger to a 4 stage smart charger) but, over 17 years we have not actually boondocked... so I'm a bit uncertain about needing the added capacity of 2 batteries.
I guess I'll have to open up the electric panel to see what is in there and then figure out if it may or may not be appropriate for charging an AGM battery.

Jason, I replaced my Group 24 with a Group 27 and it fit perfectly.

[rohrmann]

Originally Posted by Jason687

Thanks for all the helpful advice. Some further info...
My rig came with a single group 24 deep cycle marine battery. Looks like the box could accommodate a group 27. I'm considering replacing with a UB1210000 AGM 12V battery (or possibly two of them).

I did install two 6V batteries in our last 5th wheel (and upgraded the charger to a 4 stage smart charger) but, over 17 years we have not actually boondocked... so I'm a bit uncertain about needing the added capacity of 2 batteries.
I guess I'll have to open up the electric panel to see what is in there and then figure out if it may or may not be appropriate for charging an AGM battery.

The AGM batteries use the same charging as any lead acid battery. A gel cell or a lithium battery use a different charging format.

[Dave W]

At that vintage, it possibly has a WFCO 9800 series converter rather then an integrated 'power center'. There is a fair amount of information on the 'net about their operation. They are pretty reliable though the cheap 12VDC ADDA fans they use for cooling can vibrate and get noisy - I have 2 converters waiting for my attention and new fans. These converters have a float ability and will not overcharge your battery.


Battery size - I usually install a Group 29/31 though the current one is a Gr27 due to availability when needed. Whichever one is used, the trailer is left plugged in 24/7/365

[laverdur]

My 2012 3150RL came with a multi-stage converter. Unless towing, my rig stays plugged in to shore power and I've never fried a battery. That said, I use Centennial batteries (2) which are true maintenance-free batteries. If using other batteries, the battery electrolyte level should be checked periodically and topped up with distilled water so that you can keep the plates covered.

[Leftie Canuk]

For what's worth, our 2012 3150RL has what appears to be a decent multi-stage charger that floats our 2 x 6v deep cycle batteries, and previously floated two Grp 27 12V batteries. This charger is quiet - no fan noise, no drama.
My suggestion is to leave your shore power connection in place as long and often as possible, and check the electrolyte levels frequently one dry cell can ruin your day !

[trevorhutton106@gmail.com]

I have a Big Sky 340RLQ. It has two 12 volt batteries (recently replaced), a solar panel that always reads 13 to 15 volts and a Xantrex converter but cannot see the model number. When shore power fails the batteries loose their charge in a few hours. How do I test the converter in this configuration. Many thanks, Trev.

[Carl n Susan]

It would help if you listed the year of your Big Sky. I am not a solar expert. But I thought a solar system included a charge controller that charges the batteries. Many solar users disconnect the stock converter in favor of the charge controller. But someone more knowledgeable than I will be along to comment

[trevorhutton106@gmail.com]

Thanks Carl. It is a 2008 model. Trev

[Carl n Susan]

Assuming you still have the stock converter (the Xantrax) you can:

• With shore power connected, check the output voltage on the converter where the 12V circuits connect. It should be 13.4V or more.
• With shore power still connected, check voltage at both sides of the two red plastic covered self-resetting circuit breakers behind the battery *AND* the voltage at the battery. All readings should be 13.4V or more.
• Remove the shore power, wait 15 minutes for the surface voltage to equalize, then check the two self-resetting circuit breakers and the battery again. They should now be around 12.4V.

If all checks out, take the batteries to someone who can load test them.

[Leftie Canuk]

Originally Posted by Jason687

Have recently acquired a 2011 Montana 3150RL. No solar on rig. Need to replace a dead battery. First thought is to understand the charging system when connected to shore power. From the factory, did this rig use a multi stage charger that includes trickle charging once a full charge is reached, or will I burn out the battery if I leave shore power connected during winter storage?



Are there any useful after market upgrades other owners have made to the charging system to improve effectiveness?


Thanks in advance for comments/help in understanding.

Jason,
Welcome to the Montana club !

I have a 2012 3150RL and have not had much luck with my recently-installed Trojan 105 batteries in series. I am now wondering if the converter is the culprit.
Have you found the physical location of the converter in your rig ? I ask because the troubleshooting steps in the user manual include checking the converter's on-board fuses if there is no DC output. Any location knowledge gratefully received.

[Carl n Susan]

Originally Posted by Leftie Canuk

Jason,
Welcome to the Montana club !

I have a 2012 3150RL and have not had much luck with my recently-installed Trojan 105 batteries in series. I am now wondering if the converter is the culprit.
Have you found the physical location of the converter in your rig ? I ask because the troubleshooting steps in the user manual include checking the converter's on-board fuses if there is no DC output. Any location knowledge gratefully received.

Your 2012 has the same converter as my, and everyone else's, 2012 Montana. It is a Progressive Dynamics PD45 power distribution system which includes the 120V AC circuit breakers, 12v DC fuses, and the integrated converter.

The manual in the Files section titled "Progressive Dynamics converter troubleshooting" applies to your RV. Take a look at https://www.montanaowners.com/forums...?do=file&id=58 and Download the PDF.

The Power Panel is usually located near the floor adjacent to the steps to the bedroom. But it does move around on some specific models.

[Dave W]

With either a PD or WFCO converter there are three wires. One is a bare ground while the other and insulated two go to the battery. One of those two insulated may have loosens or 'popped' loose. The converter also has a conventional though 20 amp plug cord that plugs on the back of the power center. That may have 'popped' loose. Unfortunately you may have to pull that power center out to check/ 4 tiny screws for the cover and 4 larger ned to pill the center from the wall. Any other brand converter will be similar

Then those fuses- there are two on the WFCO and three pn the PD and in both cases near the battery wires. These will fail instantly if the battery wires touch if the coach plugged in or if the the batteroes are even instantly connected up incorrectly.

To confuse the issue a biy. those converters have red + and black - terminals while the RV has black + and white negative - wiring.

If you do need to change a converter, I suggest that you use a Progressive Dynamics PD9260. Ours came with a WFCO and two later, changed due to squealing and vibrating fans, installed this PD model. Yes, I replaced the $5.00 fans and now have two spare WFCOs but the new PD is so quiet ....

[twindman]

From what I can see, no one answered part of the question which I thought was the main part. If you are mostly concerned with storage you don't need to do anything special. Just disconnect the battery cable. If you are someplace cold for storage, I guess they can freeze if it gets too cold. I am in AZ don't worry about that! Anyway, many on here, myself included, store for 6 months or more with no shore power and the batteries are fine at that point.

[Dave W]

Originally Posted by twindman

From what I can see, no one answered part of the question which I thought was the main part. If you are mostly concerned with storage you don't need to do anything special. Just disconnect the battery cable. If you are someplace cold for storage, I guess they can freeze if it gets too cold. I am in AZ don't worry about that! Anyway, many on here, myself included, store for 6 months or more with no shore power and the batteries are fine at that point.

That's freezing point vs charge seen hee"https://modernsurvivalblog.com/alternative-energy/lead-acid-batteries-state-of-charge-versus-freezing-temperature/


Yes, if the batteries get too low on charge due to a nom charging converter, there is a worry and it really isn't as cold as you would magine