Battery Disconnect?

[Jrpammink]

After winterizing our 5th wheel we used the battery disconnect switch to disconnect our battery, or so we thought... we went out this past weekend and our battery is dead. Is there a reason for this or are we missing something? Thanks for your help!

[Cate&Rob]

After winterizing our 5th wheel we used the battery disconnect switch to disconnect our battery, or so we thought... we went out this past weekend and our battery is dead. Is there a reason for this or are we missing something? Thanks for your help!

The factory "battery disconnect" does not disconnect everything. The CO detector, the radio memory and other things are still powered up. These are small loads, but they will fully discharge a single battery in a week or two. Many of us have installed a true "battery disconnect switch" on either the positive or negative cable to the battery. Another alternative is to physically disconnect either the positive or negative cable from the battery. This will preserve it's state of charge.

Rob

[bertschb]

Hi and welcome to the forum. Unfortunately, you aren't missing anything. The factory battery disconnect switch doesn't disconnect the battery. Depending on your particular model, there are at least a couple systems (e.g. CO detector) that stay connected even when the switch is turned off. It's one of my few pet peeves I have with Grand Design.

Most people either remove the negative battery cable or install a second (real) battery disconnect in order to disconnect the battery. Hopefully your battery wasn't damaged.

[Jrpammink]

Thank you for your responses!

[Guest]

[QUOTE=bertschb;n10630]The factory battery disconnect switch doesn't disconnect the battery. Depending on your particular model,

Correct on model variation. My 2017 2600RB Imagine battery switch cuts all power to my rig. Guess I lucked out. In addition, there is a new and improved battery switch that has a strong detent at the end of travel to prevent power interruptions. My original switch had no detent and would spring back and lose power when traveling.

Jim

[bertschb]

Neither my 2016 nor my 2019 battery "cut off" switch cut all power. One of my first mods for the new 310GK-R will be to add a functional cut off switch.

[Kksfish]

Ok I understand the reasoning behind having “life safety “ stuff connected ahead of the battery disconnect.....today I went by the Rv storage place to connect shore power just to charge the battery since it’s been so cold here and with the disconnect in off position ALL 12volt devices worked! Just to double check myself(no vom with me) I tried
all the interior lights with the battery disconnect in both positions.....devices only went off when I disconnected shore power!
Is this how it’s supposed to operate? On previous rigs the disconnect turned everything 12volt off regardless of status of shore power!

[howson]

Ok I understand the reasoning behind having “life safety “ stuff connected ahead of the battery disconnect.....today I went by the Rv storage place to connect shore power just to charge the battery since it’s been so cold here and with the disconnect in off position ALL 12volt devices worked! Just to double check myself(no vom with me) I tried
all the interior lights with the battery disconnect in both positions.....devices only went off when I disconnected shore power!
Is this how it’s supposed to operate? On previous rigs the disconnect turned everything 12volt off regardless of status of shore power!

What's happening is your Converter is supplying 12V power to your devices while on shore power. When you disconnected shore power it (obviously) shut off. You can simulate this by turning off the circuit breaker at the power convenience center.

[Kksfish]

Thanks Howard......that makes sense! Some rainy day when I have nothing else to do guess I’ll install a second disconnect so I can charge the battery without enabling my 12volt stuff.....I like to have the shore power on a timer once a week just to keep battery charged but don’t like the idea of having everything (landing gear) operable !

[howson]

Thanks Howard......that makes sense! Some rainy day when I have nothing else to do guess I’ll install a second disconnect so I can charge the battery without enabling my 12volt stuff.....I like to have the shore power on a timer once a week just to keep battery charged but don’t like the idea of having everything (landing gear) operable !

A lot of us have done just that. It's not too hard. While you're at it swap out the OEM disconnect for a Blue Sea and there's no more accidental bumping of the key.

In my setup shutoff 2 performs exactly like the OEM's and shutoff 1 is my "kill everything" switch.

[Kksfish]

Thanks Howard! Nice one line diagram.....

[Country Campers]

Thanks Howard! Nice one line diagram.....

I think you will be a little more involved in this than you think. Howards "one line diagram" is for a TT not a fifth wheel. In the front storage where the battery is located are similar breakers that Howard has pictured. The battery connects to these breakers and then distributed off to where ever needed. When plugged into shore power that travels to the AC breaker panel and then to the converter/charger from the converter charger to the 12 volt panel beside the AC breaker panel. From the 12 volt panel it is then distributed to the RV as well as back to the battery for charging. The only way to stop all of the 12 volt items in the RV from being on when on shore power is to stop the power from the converter/charger from powering the 12 volt panel.
I think this is right and hope it makes sense.

Brian

[howson]

I think you will be a little more involved in this than you think. Howards "one line diagram" is for a TT not a fifth wheel. In the front storage where the battery is located are similar breakers that Howard has pictured. The battery connects to these breakers and then distributed off to where ever needed. When plugged into shore power that travels to the AC breaker panel and then to the converter/charger from the converter charger to the 12 volt panel beside the AC breaker panel. From the 12 volt panel it is then distributed to the RV as well as back to the battery for charging. The only way to stop all of the 12 volt items in the RV from being on when on shore power is to stop the power from the converter/charger from powering the 12 volt panel.
I think this is right and hope it makes sense.

Brian

Hmmm...I'll need to look at your 5vr in April. Theoretically it *should* be simple on your rig, too.

Edit: But of course you're right about the converter and when on shore power. My input was based on the ability to kill all power from the battery to the trailer. Killing the converter is as simple as turning off the circuit breaker.

[Kksfish]

Thanks Brian, I didn’t think about that!
I will have to investigate and ring out my current configuration, but it sounds as if I can put a disconnect after the converter and ahead of the 12V.....