Winter Battery Maintenance in a 400

Haloo

I don’t particularly want to pull the battery out of my 400 to keep it charged over the winter.  It is very heavy, and wedged into a tight space.  So while my garage stays around 50 degrees, I’d like to leave the battery in the 400. The temperatures in our area of the Puget Sound are most frequently in the upper 30s (mostly at night) to upper 40s/low 50s daytime throughout the winter.  Every once in a while the temps will dip into the 20s over night, and far less frequently (once every few years) into the teens.

So here is what I have done:
1. I flipped the battery disconnect switch.
2. I connected the trailer to shore power.  (Neither the cord nor outlets are exposed to rain.)
3. I attached a Battery Tender Plus to my battery.
4. I plugged the Battery Tender Plus into a 120 volt outlet in the 400.

Do I need to be concerned about the Converter if no 12V stuff is turned on in the 400?  Am I missing some other issue that I need to be concerned about?

Sharon_is_SAM

Why not plug the battery tender into shorepower?  

Haloo

I would have to figure out how to snake a cord into the trailer and not let any bugs, moisture, rodents, etc... into the camper.  The battery is inside the storage compartment at the back of the camper.  I know at least one way I can do it, but it is a little bit of a hassle.

BrianZ

I am wondering what is there to be gained by removing the battery &/or connecting it to another charger for storage, aside from possibly warmer & less fluctuating storage temperatures.  Granted, it's not the same type of battery as in our car's which we leave outside without benefit of a trickle charge, but they last for years. 

The Battery Tender is a 3-stage charger that can provide a trickle charge mode during storage, and I don't know what the 400 has, but my T@B converter is also a 3-stage charger with float mode that provides a trickle charge during storage. If one were comparing a single stage on/off type non-float mode charger to a 3-stage charger, then I could see a reason for using a separate 3-stage charger.

So, I ask, why not leave my T@B 320S (or your 400) plugged in to house power for the winter & let the converter maintain it (with battery switch on of course)?  Is there really a good reason to do anything else?

Haloo

BrianZ said:

I am wondering what is there to be gained by removing the battery &/or connecting it to another charger for storage, aside from possibly warmer & less fluctuating storage temperatures.  Granted, it's not the same type of battery as in out car's which we leave outside without benefit of a trickle charge, but they last for years. 

The Battery Tender is a 3-stage charger that can provide a trickle charge mode during storage, and I don't know what the 400 has, but my T@B converter is also a 3-stage charger with float mode that provides a trickle charge during storage. If one were comparing a single stage on/off type non-float mode charger to a 3-stage charger, then I could see a reason for using a separate 3-stage charger.

So, I ask, why not leave my T@B 320S (or your 400) plugged in to house power for the winter & let the converter maintain it (with battery switch on of course)?  Is there really a good reason to do anything else?

Excellent question!  Have fun with this thread:
http://tab-rv.vanillaforums.com/discussion/4200/quickest-way-to-charge-battery/p1

The short version of the thread is that the converter in our T@Bs is not a very good 3 stage charger.  

And....somewhere, on some thread, it was suggested that having the Converter operating all of the time might not be a good idea because it will shorten it’s lifespan.  Is this true?  I don’t know.  And in other threads things like temperature have been mentioned as an issue in storage.

After years of using Battery Tenders I’m pretty sure they do a decent job.  I’m willing to bow to the experience and expertise of the folks who participated in the above mentioned thread with regard to the Converter in our T@Bs.

So, I’m okay with using a Battery Tender.  But I’m wondering whether there is anything else I should be concerned about with regard to having it run off a plug in my camper while the camper is plugged into shore power.

Clearly, a person could get pretty obsessive about this — either just for fun, or because one is afflicted by obessions.   I just want to avoid doing something stupid, or particularly harmful.

Sharon_is_SAM

Haloo, I forgot the 400 battery is internal.  We have a 150 amp AGM and we will store the TaB indoors at 55 degrees without a charger.  We stored it for 2 1/2 months July to October and it remained at 100% charge.  We will just make sure it is fully charged before storing.  The AGMs have such a low self discharge that I think this will work until we take it out of storage in early March.  I can’t remember if the AGM receives any kind of a necessary equalization charge on the smart chargers.  Anybody know?

Ratkity

AGM (unless one specific brand) do not need equalization. They also hold a charge for months whereas the flooded lead-acid batteries need a tender and lose charge without one. The key is to have a battery cut-off switch and flip it before storage. Once out of storage, give the battery one good overnight charge with a regular charger and you are good to go! AGMs are maintenance-free. You don't have water levels to check.

Haloo

Well, maybe I'll just unplug from shore power and reconnect every few weeks to charge my battery with my tender. The battery cutoff switch has already been flipped.

Thanks!

atlasb

We use a battery tender type unit that has the 12v AGM setting and also a winter setting.  When we pull the 400 back into the shop after a trip, I always reconnect the tender.  When not in use, it is always plugged in.  Did the same with our 320 and seemed to work well.  I used one of the connectors like for the solar connectors that came with the charger and wired it directly to the battery.  Then I can disconnect when ready to go.  I don't turn the battery disconnect switch so I can have lights when I want do do something in the trailer.  Any one see any problem as it seems good so far.  Just not used to AGM batteries and have searched for information on them and seems to be a lot to sort through. Did find a price listing for our battery and at $650,  Don't plan to replace any time soon.

Sharon_is_SAM

Not sure about your device, but my 5 Amp Battery Tender - Power Tender said not to run any loads while connected to the charger.  So, I isolate the battery whenever I want to charge and use the TaB systems at the same time.  

Haloo

atlasb said:

We use a battery tender type unit that has the 12v AGM setting and also a winter setting.  When we pull the 400 back into the shop after a trip, I always reconnect the tender.  When not in use, it is always plugged in.  Did the same with our 320 and seemed to work well.  I used one of the connectors like for the solar connectors that came with the charger and wired it directly to the battery.  Then I can disconnect when ready to go.  I don't turn the battery disconnect switch so I can have lights when I want do do something in the trailer.  Any one see any problem as it seems good so far.  Just not used to AGM batteries and have searched for information on them and seems to be a lot to sort through. Did find a price listing for our battery and at $650,  Don't plan to replace any time soon.

I put a Battery Tender pigtail on my battery as well.  If I were storing it inside I’d just run an extention cord into the storage compartment.  Unfortunately, I don’t have a fancy schmancy shop in which to store my camper like some people on this forum.  

I’d be inclined to turn everything off in my camper and just have the tender hooked up if I were storing the camper indoors — just to keep all of the electronics off that I didn’t really need to keep on.  But this sounds fussy even to me.  No load on the battery while charging, as Sam says?  I dunno.  What about while it’s just maintaining?  Inverters, converters, regulators, 12V, 120V, bulk charge, trickle charge....

I’m just happy the truth about margarine has come out and I can eat butter again.

Sharon_is_SAM

Haloo, I just turn the battery cut-off switch to OFF, place the charger, and run the inside off shorepower.  Not sure why you can't have a load while charging, but I am guessing, it may have something to do with drawing too much current and creating a fire.  You can still leave your 400 plugged in and charge at the same time.

Haloo

SAM said:

Haloo, I just turn the battery cut-off switch to OFF, place the charger, and run the inside off shorepower.  Not sure why you can't have a load while charging, but I am guessing, it may have something to do with drawing too much current and creating a fire.  You can still leave your 400 plugged in and charge at the same time.

Thanks!  I am going to consider this the absolute, final, definitive answer...until someone else weighs in.  

Ratkity

The camper has a charger and then you are adding another charger. You are having competing chargers going. Then you have a load. Keep it simple. Turn off the battery cutoff, do a full overnight charge with an independent charger and then leave it for the winter. Give it another full overnight charge after you wake up your camper for spring. That's all you have to do to. If you want to work in the camper, plug it in. It's not going to adversely affect the charge of the battery because of the onboard charger. 

Haloo

Ratkity said:

The camper has a charger and then you are adding another charger. You are having competing chargers going. Then you have a load. Keep it simple. Turn off the battery cutoff, do a full overnight charge with an independent charger and then leave it for the winter. Give it another full overnight charge after you wake up your camper for spring. That's all you have to do to. If you want to work in the camper, plug it in. It's not going to adversely affect the charge of the battery because of the onboard charger. 

From my manual (with my underlines):

Battery Disconnect Switch

The battery disconnect switch is used to separate the batteries from the 12-volt distribution panel and converter charging system.

When the switch is turned to ON and the trailer is plugged into a 120-volt shoreline, the 12-volt distribution panel will receive power from the converter and the batteries will be charged through the converter charging system.  

When the switch is turned to OFF and the trailer is plugged into a 120-volt shoreline, the 12-volt distribution panel will still receive power from the converter, but the batteries are disconnected from the system. The batteries will not be drained with the switch in the OFF position. The converter will not charge the batteries with the switch in this position. 

Do I need to be concerned that the Converter is still connected to power even though it isn’t charging the battery (my battery switch is off) and I have nothing else running in the camper?  Two reasons I ask this.  1. Someone mentioned in one of the numerous battery and charging posts I read that it might not be a good idea to leave the Converter plugged into power even if it’s not being used.  2.  I don’t have anything else to obsess about this morning.  

Or I may do as you say and just unplug everything, and charge up the battery occassionally.

Sharon_is_SAM

So, is there wear and tear on the converter when it is not charging the battery? 
Here are some potential loads to think about.  I got this from an old post that I saved from a 2015 320 S model.   The CO/LP detector and any other phantom loads from the television, USB plugs, Alde and converter system detection circuit, tank/battery monitors.  How much these require from the converter???

Ratkity

OMG.. my head just exploded. I didn't know the 110V plugged in shore power would still be powering all things, but just not charging the battery. It would still use the converter. Wear and tear? No clue. 

Haloo

Ratkity said:

OMG.. my head just exploded. I didn't know the 110V plugged in shore power would still be powering all things, but just not charging the battery. It would still use the converter. Wear and tear? No clue. 

Yeah, it’s like hold it, what?  With the factory solar there are 3 charging systems (from the TV, solar, shore power) on board the 400 that sometimes overlap and sometimes don’t.  Some of this electronic stuff is expensive and complicated, so it has left me scratching my head.

After doing a little more Internet research and poking around on this forum, here is what I’ve decided to do:

1.  I’ve topped up our onboard AGM battery with a battery tender.  AGMs have a low discharge rate when disconnected, and...
2.  I’ve already flipped the battery disconnect switch to “Off”.
3.  I’m going to disconnect all power to the camper -  We live near the end of a long power distribution line.  In the winter we are vulnerable to wind storms that interrupt power and cause surges. I haven’t yet installed a surge suppressor in our trailer (I want to install a permanent suppressor after reading forum input), and don’t have the time to figure out how to do it right now.
4.  Every month or so I’m going to reconnect my battery tender and top off the battery.  AGMs don’t have a big sulfation problem, expecially when they don’t go through a deep discharge cycle.  So keeping it pretty well topped up seems like a healthy thing to do for the battery.
5.  Reconsider the joys of tent camping.  Just kidding.  We love our 400!

rfuss928

We just finished our sixth season with two Optima AGM batteries.  Both batteries were tested at a service center this spring and were still better than new specs.

This is what I do:

I do not plug in the trailer. Basically to not run the 25 amp converter for five or six months for less than one amp parasitic loads. 
I connect a quality maintainer with a de-sulfation pulse to the batteries which are still connected to the trailer.  I use 12v devices in the trailer with no concerns on the infrequent visits during storage.  The maintainer easily keeps the batteries full with this light use.
For the other six months SUNT@B is plugged in at home or camping and charging/maintaining from the converter or solar.

 I'm very satisfied with the absolutely maintenance free longevity of the batteries and simply offer this as an approach that has worked well for me.  I have easy access to power while in storage which enables this method. 

Michigan_Mike

SAM said:

So, is there wear and tear on the converter when it is not charging the battery? 
Here are some potential loads to think about.  I got this from an old post that I saved from a 2015 320 S model.   The CO/LP detector and any other phantom loads from the television, USB plugs, Alde and converter system detection circuit, tank/battery monitors.  How much these require from the converter???

I doubt either of those two devices would place any real wear and tear on the converter.   When a load or resistance is placed on an electrical circuit it can create heat.  It's been my experience in the electrical field that extended periods of heat and heating does have an impact on things over time.  As an example and here in the Midwest (working for the power company), when we experienced long stints of excessively hot weather we'd have transformer and equipment failures just from heat alone and via circuit loads from air conditioning units, etc.  It was interesting because after the heat had subsided we'd still experience equipment failures 4-5 days after things cooled down....  On a smaller scale via the inverter, if it is left on for extended periods of time, is charging the battery or used via trailer components it probably does experience some wear and tear, as opposed to if it were sitting unplugged and idle.

Haloo

rfuss928 said:

We just finished our sixth season with two Optima AGM batteries.  Both batteries were tested at a service center this spring and were still better than new specs.

This is what I do:

I do not plug in the trailer. Basically to not run the 25 amp converter for five or six months for less than one amp parasitic loads. 
I connect a quality maintainer with a de-sulfation pulse to the batteries which are still connected to the trailer.  I use 12v devices in the trailer with no concerns on the infrequent visits during storage.  The maintainer easily keeps the batteries full with this light use.
For the other six months SUNT@B is plugged in at home or camping and charging/maintaining from the converter or solar.

 I'm very satisfied with the absolutely maintenance free longevity of the batteries and simply offer this as an approach that has worked well for me.  I have easy access to power while in storage which enables this method. 

This is what I’d do if my battery wasn’t inside the camper.  Because it is I’d have to figure out how to get the charger cord into the camper through a weather, bug, and rodent proof opening.

Sharon_is_SAM

Haloo, sounds like a good plan.  Please keep us posted how that works out.  

rfuss928

Haloo
My batteries are also inside the T@B in the bottom of the closet and sealed in vented boxes.



I connect the maintainer to a SAE 2 pin connector that is permanently installed to the battery wiring.
 

I feed a flat extension cord through the side window and close the window.  I've never had any pest problems which are common around the shed where it is stored.  The maintainer plugs in the extension cord.

Many of the new T@Bs have a solar panel connection outside.  A maintainer could easily be adapted to connect there. 

You can also make the battery connection at the 7-pin connector.  I sometimes connect my supplemental solar panel there.

Sharon_is_SAM

Bob, how do use the trailer pigtail to connect to a smart charger or solar?

Haloo

@rfuss928  Many of the new T@Bs have a solar panel connection outside.  A maintainer could easily be adapted to connect there.  

I think this is what I may do if I find the time and have some decent weather in a few weeks.  Thanks for the idea!

BTW, I lived on Amity Street when I was in 2nd, 3rd, and 4th grade. Spencerport was kid heaven back in the early 60s. 

rfuss928

SAM said:

Bob, how do use the trailer pigtail to connect to a smart charger or solar?

I connect to the 12v and GRD terminals in the plug which are connected directly to the battery.
For some time I improvised spades to make the connections in the plug. 
Now I have a mating socket wired for the connections I just plug the pigtail into when needed.

https://www.amazon.com/58150-7-Way-Blade-Connector-Socket/dp/B001EP0G72/ref=sr_1_5?ie=UTF8&qid=1510543287&sr=8-5&keywords=7+pin+trailer+connector

Sharon_is_SAM

This would be very handy since we disconnected our tub solar outlet which now runs to a solar controller.  Can you give more details and pics?

rfuss928

SAM said:

This would be very handy since we disconnected our tub solar outlet which now runs to a solar controller.  Can you give more details and pics?

The wiring diagrams are in a .pdf attached a few posts back.
An Amazon link to an example of the socket is also above.
Here is a photo of the adapter I made.

Just plug the trailer pigtail in this and connect your charger or solar.

Initially I just connected the clips from my charger to the bare ends of the black and white wires.  It was a quick work around when I had a converter failure while on a trip.  I recently added the 2 pin SAE connector for my portable solar hook-up.

Sharon_is_SAM

Thanks Bob.  I need to look into  doing this.

BrianZ

Haloo said:

BrianZ said:

I am wondering what is there to be gained by removing the battery &/or connecting it to another charger for storage, aside from possibly warmer & less fluctuating storage temperatures.  Granted, it's not the same type of battery as in out car's which we leave outside without benefit of a trickle charge, but they last for years. 

The Battery Tender is a 3-stage charger that can provide a trickle charge mode during storage, and I don't know what the 400 has, but my T@B converter is also a 3-stage charger with float mode that provides a trickle charge during storage. If one were comparing a single stage on/off type non-float mode charger to a 3-stage charger, then I could see a reason for using a separate 3-stage charger.

So, I ask, why not leave my T@B 320S (or your 400) plugged in to house power for the winter & let the converter maintain it (with battery switch on of course)?  Is there really a good reason to do anything else?

Excellent question!  Have fun with this thread:
http://tab-rv.vanillaforums.com/discussion/4200/quickest-way-to-charge-battery/p1

The short version of the thread is that the converter in our T@Bs is not a very good 3 stage charger.  

And....somewhere, on some thread, it was suggested that having the Converter operating all of the time might not be a good idea because it will shorten it’s lifespan.  Is this true?  I don’t know.  And in other threads things like temperature have been mentioned as an issue in storage.

After years of using Battery Tenders I’m pretty sure they do a decent job.  I’m willing to bow to the experience and expertise of the folks who participated in the above mentioned thread with regard to the Converter in our T@Bs.

So, I’m okay with using a Battery Tender.  But I’m wondering whether there is anything else I should be concerned about with regard to having it run off a plug in my camper while the camper is plugged into shore power.

Clearly, a person could get pretty obsessive about this — either just for fun, or because one is afflicted by obessions.   I just want to avoid doing something stupid, or particularly harmful.

Thanks, Haloo, for that thread link, which I read thoroughly.  I found Wizzard's in depth replies interesting about the difficulties he described with the WFCO converter/charger.  It gave me expectations that I would likely not see our converter drop down its voltage into float/trickle charge mode without first removing all the fuses.  So, after having winterized our 3-month old T@B 320s, & having already left it plugged in & charging for a week or more, I still needed to decide about this issue of how I would maintain the battery over the winter.  

I decided to try removing the fuses, but first I would check voltages on the monitor & by measuring at the battery with a voltmeter.  To my pleasant surprise, the converter was already in float mode!  Despite the various detectors, LEDs, LCD & LED displays, etc, that were still receiving power, it was not enough of a load apparently to prevent the system from switching to 13.2 volts on the monitor display and 13.02V measured at the battery.  The difference is what one would expect due to resistance in the 10 gauge wiring. 

So, I have my answer & plan to leave the power plugged in to house power over the winter.  I'm not concerned about the small amount of amperage flowing in the trailer circuits, as I believe it's not enough to cause any significant amount of heat or "wear & tear" on components.  I doubt battery life will suffer to any significant degree, nor do we have any need for charging the battery to its max level, since we expect to generally only be using hookups in the future.