shore power with battery disconnected?

[Ivan S854]

We recently ran a 50 amp service out to our barn where our trailer is stored.

I've read where I shouldn't leave the shore power connected for extended periods of time when the trailer isn't being used... something about the battery being overcharged by the trailer charger?

I would like to leave the shore power going without the battery in the loop...
So, can I disconnect the battery, leave it in place and use my Battery Tender to keep it topped up? All the while, leaving the 50 amp service hot...

[jmbopp]

Yes, the WFCO converter doesn't need a battery connected for proper operation. But I leave my trailer plugged in all summer between trips and just check the battery water level now and then.

[JCR GD]

Same here. Leave it hooked up and check it occasionally. The converters work pretty well at dropping down to just trickle charge.

[WhittleBurner]

We stay for 6 months in Florida every winter hooked up the whole time. No problems. Do like jmbopp suggested though and check the battery level on occasion. I probably check ours once every 6 months.

[Second Chance]

Those of us who full-time in our rigs (and don't boondock) have the rigs connected to shore power all the time without disconnecting the battery. The converter/chargers are multi-stage charges and go into a maintenance mode when the battery is fully charged. As stated above, check the electrolyte levels in the battery regularly and you're good to go.

Rob

[KY Gentleman Farmer]

Those of us who full-time in our rigs (and don't boondock) have the rigs connected to shore power all the time without disconnecting the battery. The converter/chargers are multi-stage charges and go into a maintenance mode when the battery is fully charged. As stated above, check the electrolyte levels in the battery regularly and you're good to go.

Rob

Hi Everyone, have done lots of reading about batteries recently due to having cooked mine over the summer and having just replaced it. It appears the following are true:

1. Letting batteries get too discharged is bad.
2. Overcharging batteries (e.g., leaving them connected to shore power full time) is bad, UNLESS
3. Your RV has "smart charging" or "battery minder" capabilities.

I have read my manual (2020 315RLTS) and can't find anything that describes whether it has these capabilities, or whether it implements the Bulk-Absorption-Float approach to battery charging. However, based on the dates of various posts here on our beloved forum, I am inclined to believe that my system DOES have this capability, and that leaving it connected full-time to shore power with the Disconnect Switch in the "On" position will therefore not adversely affect my (new!) battery's life.

Does this sound about right? Does anyone know when/if GD started installing "smart charging" capabilities? Does it depend on the particular model? Thanks in advance!

[sande005]

Most RV's have a converter made by WFCO. It may take a bit of detective work to find the specific model in yours. In any event, here's a link to the general information about how the converters charge a battery, from WFCO: https://wfcoelectronics.com/theory-of-operation/
For a deeply discharged one, it will charge at a high rate (Bulk) for up to 4 hours, then drop to an absorption rate for up to 44 hrs, then drop to a long term trickle (float) rate.
Some feel that the WFCO converters, being less expensive, may be more prone to failure, resulting in damaged batteries. It's kind of like the great tire debate - many, many using them for years with no issues. And some that do experience a problem.....

[Second Chance]

Hi Everyone, have done lots of reading about batteries recently due to having cooked mine over the summer and having just replaced it. It appears the following are true:

1. Letting batteries get too discharged is bad.
2. Overcharging batteries (e.g., leaving them connected to shore power full time) is bad, UNLESS
3. Your RV has "smart charging" or "battery minder" capabilities.

I have read my manual (2020 315RLTS) and can't find anything that describes whether it has these capabilities, or whether it implements the Bulk-Absorption-Float approach to battery charging. However, based on the dates of various posts here on our beloved forum, I am inclined to believe that my system DOES have this capability, and that leaving it connected full-time to shore power with the Disconnect Switch in the "On" position will therefore not adversely affect my (new!) battery's life.

Does this sound about right? Does anyone know when/if GD started installing "smart charging" capabilities? Does it depend on the particular model? Thanks in advance!

You won't find the details on your converter/charger in the RV manual from GD. You should, however, find a small manual for the WFCO converter/charger in the bag of other paperwork that came with your unit. If you can't find that, you should be able to find the model number of the converter/charger on the Serial Number Data Sheet that came with your RV when it was new. You can then go to the WFCO web site and download a PDF copy of the manual. Bottom line is GD has always installed stepping converter/chargers in their RVs and, yes, they charge based on the needs of the battery. You just need to check regularly to make sure the battery is topped off with distilled water.

Rob

[Redapple63]

Hi Everyone, have done lots of reading about batteries recently due to having cooked mine over the summer and having just replaced it. It appears the following are true:

1. Letting batteries get too discharged is bad.
2. Overcharging batteries (e.g., leaving them connected to shore power full time) is bad, UNLESS
3. Your RV has "smart charging" or "battery minder" capabilities.

I have read my manual (2020 315RLTS) and can't find anything that describes whether it has these capabilities, or whether it implements the Bulk-Absorption-Float approach to battery charging. However, based on the dates of various posts here on our beloved forum, I am inclined to believe that my system DOES have this capability, and that leaving it connected full-time to shore power with the Disconnect Switch in the "On" position will therefore not adversely affect my (new!) battery's life.

Does this sound about right? Does anyone know when/if GD started installing "smart charging" capabilities? Does it depend on the particular model? Thanks in advance!

Gentlemen Farmer,

Your assumptions are correct.

We have the same rig, mine is a 2020 model.

I have replaced the stock converter/charger which is a WFCO 9855.

These are supposed to be three stage chargers, but for some reason mine never goes into float mode. I made the choice to swap it out after it cooked my batteries for the third time.

The converter for our rig is a deck mount and it’s screwed vertically in the space under the hutch area.

My replacement of choice was the Progressive Dynamics 9260. It is awesome. I have checked my batteries every three months and they are full. Never been cooked since the replacement

Let me find the picture of the original. Don’t think I have one after it was swapped.

[KY Gentleman Farmer]

Gentlemen Farmer,

Your assumptions are correct.

We have the same rig, mine is a 2020 model.

I have replaced the stock converter/charger which is a WFCO 9855.

These are supposed to be three stage chargers, but for some reason mine never goes into float mode. I made the choice to swap it out after it cooked my batteries for the third time.

The converter for our rig is a deck mount and it’s screwed vertically in the space under the hutch area.

My replacement of choice was the Progressive Dynamics 9260. It is awesome. I have checked my batteries every three months and they are full. Never been cooked since the replacement

Let me find the picture of the original. Don’t think I have one after it was swapped.

Thx for the info gang, resolved a number of lingering questions I had about how best to maintain my battery/electrical system, sincerely appreciate it.
@Redapple63, how did you determine your converter wasn't going into float mode (other than the cooked batteries, I mean)? Did you measure output somewhere?