Battery disconnect switch purpose on Momentum

[orbiker]

THANK YOU!

Going out to the basement now ( camping by the ocean here in Monterey, CA ). Setting the key to OFF ( batteries supplying power to trailer ), and will leave it like this until we get it back to storage, at which time I’ll disconnect the neg cable from the trailer.

NEVER TOUCHING THE KEY AGAIN NOW. [emoji51][emoji2]


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Setting the key to ON ( batteries supplying power to trailer )
Just turn the key to ON and never touch it again, except to make sure it's always on. Remember; if the key is not on, the converter is NOT charging your batteries.
KEN

[JCR GD]

Problem is those switches (at least some of them) are called "disconnect" switches that say "ON" is disconnected. Very confusing. Reverse of what most of us would think. I think OP has it correct now

[CaliMClass]

Thanks again to everyone who helped me with this.

We’re back home having had a much less stressful experience thanks to having working house batteries. It might be a few weeks since the trailer gets use again so I disconnected the trailer negative cable on the battery once it was settled at the storage place.

Got back to the house, put everything away and settled in for a Sunday afternoon football game.

“Oh no! I forgot to empty all the drawers in the bedroom!!” says the wife 2 minutes after I turned the TV on.

Guess who’ll be going to the storage place and reconnecting the battery tomorrow so we can open the slide in order to have clothes this week? This guy. [emoji2321][emoji1787]


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[livinthelife]

Thanks again to everyone who helped me with this.

We’re back home having had a much less stressful experience thanks to having working house batteries. It might be a few weeks since the trailer gets use again so I disconnected the trailer negative cable on the battery once it was settled at the storage place.

Got back to the house, put everything away and settled in for a Sunday afternoon football game.

“Oh no! I forgot to empty all the drawers in the bedroom!!” says the wife 2 minutes after I turned the TV on.

Guess who’ll be going to the storage place and reconnecting the battery tomorrow so we can open the slide in order to have clothes this week? This guy. [emoji2321][emoji1787]


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Yeah, my husband has taken to waiting for my "I forgot......." comment once we get back home after dropping the rig at the storage place.

It's been everything from the frozen green peppers in the freezer, to bread in the bread drawer, to dirty towels/clothes in the closet.

[jjbbrewer]

The easiest thing to remember is to just leave the red key in all the time and disconnect the battery cable for storage. Don't over think it :-)

Ok, I want to understand this parasitic draw issue better. In my previous toy hauler, I would disconnect the positive side of the batteries at the terminals and disconnect them from each other. That worked fine even for months of storage.

When I got my 349M, I was excited to find a battery disconnect switch in the storage area. Yipee! But now everyone here is saying it doesn't really disconnect everything and there's still a drain. The manual says to turn off the battery disconnect AND to disconnect the batteries AND to remove the batteries. Ugh.

So if the battery disconnect doesn't really disconnect the battery, my question is the same as this little girl's. "What does the disconnect do?"

https://d3npuic909260z.cloudfront.ne...2/268/wPDf.mp4

[AZCamper]

Ok, I want to understand this parasitic draw issue better. In my previous toy hauler, I would disconnect the positive side of the batteries at the terminals and disconnect them from each other.

When I got my 349M, I was excited to find a battery disconnect switch in the storage area. Cool. But now everyone here is saying it doesn't really disconnect everything and there's still a drain. The manual says to turn off the battery disconnect AND to disconnect the batteries AND to remove the batteries.

So if the battery disconnect doesn't really disconnect the battery, my question is the same as this little girl's.

https://d3npuic909260z.cloudfront.ne...2/268/wPDf.mp4

lol on the video. I have an electric only fridge and haven’t verified, but I have seen other trailers that when using the battery disconnect, it still allows the fridge to run. So trust but verify the battery disconnect is truly disconnecting battery power to the trailer.


‘21 Momentum 31G

[orbiker]

Thanks again to everyone who helped me with this.

We’re back home having had a much less stressful experience thanks to having working house batteries. It might be a few weeks since the trailer gets use again so I disconnected the trailer negative cable on the battery once it was settled at the storage place.

Got back to the house, put everything away and settled in for a Sunday afternoon football game.

“Oh no! I forgot to empty all the drawers in the bedroom!!” says the wife 2 minutes after I turned the TV on.

Guess who’ll be going to the storage place and reconnecting the battery tomorrow so we can open the slide in order to have clothes this week? This guy. [emoji2321][emoji1787]


Sent from my iPhone using Tapatalk

Why take everything out.
We only remove all the food out of the frig, clean it out and leave the door open a bit. We make sure there are no other perishable food in the cupboards, clean the floors etc and lock it up. KEN

[bertschb]

So if the battery disconnect doesn't really disconnect the battery, my question is the same as this little girl's. "What does the disconnect do?"

It disconnects almost everything. Depending on the rig, it won't disconnect the stereo (clock still runs) and CO detector. On some rigs it won't disconnect the power to the rear camera (if installed). Could be a couple other things. IMO, Grand Design should REMOVE the "battery disconnect" switch. I can't tell you how many people have started threads here to let us know their batteries died after 2 weeks in storage even though they flipped the disconnect switch.

[RV Sailor]

Good plan, thx to the others who responded. I'll add a couple of wrinkles.

First, you said above that you'd disconnect the battery cable "when storing for more than a couple of weeks". If you had just one 12V battery as most trailers do when delivered, that would be enough time to kill the battery. The parasitic draws that slowly drain the battery vary, but a rough rule of thumb is about 2 amps per hour, twenty-four hours per day... simple math to figure out how long your battery will last.

Since IIRC you have more battery, leaving them connected probably won't kill them in a couple of weeks but it will drain them needlessly. Batteries have a finite number of charge/discharge cycles - no point in wasting them - so you might consider disconnecting yours whenever leaving the trailer for more than a few days.

The second consideration is to touch that untouchable key one more time, when you replace it with a better battery switch and/or re-wire that one to completely disconnect your batteries. No more bending over in the dark cramped front compartment with a wrench undoing battery connections. Simply turn the switch in the basement and the batteries are fully disconnected.

Some people simply re-wire the OEM battery switch to do that job. Others of us have installed one of the switches from Blue Sea Systems:

https://www.bluesea.com/products/9001e/e-Series_Selector_Battery_Switch

These switches are REALLY well-made, smooth and sure, no arcing, no key to fall out.

The one I linked is rated for 350 amps and has some flexibility to turn on either one or both of two batteries or banks of batteries. Other switches from the company handle just one battery/bank, but there's no downside (other than possible future brain farts) to using the two-bank switch for one bank.

Sure, replacing or rewiring the switch is a bit more ambitious but it's not a gargantuan task. Some battery cable and terminal ends, maybe a nice new switch, and an hour or two of puttering and you'll have a Better Life.

Good luck.

I second this. Exactly what we did. Simple well made Blue Sea on off switch.

[jjbbrewer]

I can't tell you how many people have started threads here to let us know their batteries died after 2 weeks in storage even though they flipped the disconnect switch.

After reading this thread yesterday, I went and fetched the battery out of my 349M.

I apologize for going on and on here - it might be too involved for just a discussion about storing & using your RV. I'm planning on boondocking & being off grid for awhile.

I've had my RV in storage since December 22nd, so almost 5 weeks with the temp ~10-20deg F at night and maybe ~40 during the day. When I stored it, I ran the hydraulic leveling jacks, then switched off the disconnect switch. Everything else that I don't know about on the battery side of the switch remained connected.

I brought the battery home and it was at 12.12V open circuit, which means it was at about 40% charged (60% discharged). It's a Deka DC27 so about a 90 Ah battery. Rough calculation says it lost about 54 Ah so that would be about a 66mA continuous parasitic drain (0.8W @ 12V).

So for now, I'm not going to get too worried about messing with battery cables if my rig is going to be sitting for a month or less.

Also I'm going to order up one of the AiLi battery monitors discussed in https://www.mygrandrv.com/forum/show...or-from-Amazon