When to use the battery disconnect.

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Tiercel

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This may not be a real technical issue but it seems I have read statements like “The battery disconnect should be used for long-term storage (a month or more).”

If I am not in my MH and I am not plugged to my 15 amp extension cord, I hit the battery disconnect. Is there any reason I would not want to eliminate all little hidden drains on the battery when all I have to do is tap a switch on the way out the door?
 
Nope, I disconnect mine whenever it is not in use.
edit: As you say, you are not plugged in ;)
 
Last edited:
This may not be a real technical issue but it seems I have read statements like “The battery disconnect should be used for long-term storage (a month or more).”

If I am not in my MH and I am not plugged to my 15 amp extension cord, I hit the battery disconnect. Is there any reason I would not want to eliminate all little hidden drains on the battery when all I have to do is tap a switch on the way out the door?
The converter keeps your battery charged. The battery will discharge more if you use the disconnect while having shore power as then it cannot charge. The "shelf life" of the battery charge.

It discharges less when you use the disconnect when in storage as then the ONLY drain is the shelf life.

-Don- Marianna, FL
 
Unless I am working on the RV or running an electric heater on a cold night I unplug shore power (because I have an old converter) and hit the disconnect even though I will likely hook everything back up the next day.

I guess if I hit the battery disconnect the battery is protected from over-charge even it I am still hooked up to shore power. Is that true?
 
Mine always stays plugged in, and the only time the battery is disconnected is when I am doing maintenance. Of course I also leave the refrigerator running full time too, ...
 
In addition to the disconnect relay I have also installed a knife switch that cuts everything as if I pulled the connector from the battery terminal. I try to remember to pull this switch every time I leave my RV. It is when I forget to do this that I run into trouble.
 
I guess if I hit the battery disconnect the battery is protected from over-charge even it I am still hooked up to shore power. Is that true?
Assuming your converter is working as it should, it will never overcharge the batteries but will keep them fully charged.

IMO, they should label the switch as "storage" and "use" . That would avoid any possible confusion and questions about that switch.

Calling it a "disconnect" is like a "kill switch" on a motorcycle. If it's "on", does the bike run or not?

They need better labels. "Engine off" and "Engine on" would make more sense too.

-Don- Marianna, FL
 
Keep in mind there are often at least a couple of items such as the hardwired LP and CO detector(s) that may be connected directly to the battery instead of disconnecting through the solenoid. It's also not unusual to find aftermarket accessories wired directly as well. Joel's knife switch and other manual switches connected directly to the battery, often at the ground post for simplicity, are the only complete disconnects short of pulling a terminal off.
 
I guess I might get a better feel for the converter since I installed a battery monitor, but I hear people say they will evaporate your battery dry with an old single-stage converter. I have not noticed that, however, with my limited experience. However, that is why I pull the shore power and hit the battery disconnect if I am not in the MH or if I am not running heat or AC in my absence.
 
I guess I might get a better feel for the converter since I installed a battery monitor, but I hear people say they will evaporate your battery dry with an old single-stage converter. I have not noticed that, however, with my limited experience. However, that is why I pull the shore power and hit the battery disconnect if I am not in the MH or if I am not running heat or AC in my absence.
The older Magnetek/Parallax converters had a failure mode that could boil batteries dry, but even those were ok when they worked properly. The did have a tendency to run too hot though. Fortunately, there are upgrade kits available for them.

 
Don, it translates into me wanting to be able to grab a cold drink out of the refrigerator when I am working on the coach, or to be able to easily fire up the water heater and take a shower, as I keep it in a metal shed on the family cattle ranch about a dozen miles from my house. The motorhome also acts as an emergency escape life boat, in case of hurricane, etc. so we keep it somewhat stocked and ready to travel, if needed, though with limited food items.
 
When i store my trailer i Use the battery disconnect and put the battery on a maintainer (slow charging device). I like to keep my refrigerator doors open when in storage. With the battery connected, I can’t because the light in the refrigerator stays on.
 
I made the mistake of just keeping my MH plugged and and not having a smart inverter and it burned through my batteries. I had to get a brand new set. Luckily there is a smart add on to the inverter to take care of that situation in the future.
 
I made the mistake of just keeping my MH plugged and and not having a smart inverter and it burned through my batteries. I had to get a brand new set. Luckily there is a smart add on to the inverter to take care of that situation in the future.
You must mean converter.

-Don- Marianna, FL
 
The original question is to disconnect for a day or two, or overnight?

The little parasite drains on the battery are so slight you will barely even be able to measure them for a short period like a day. The disconnect is useful when the parasite drains are given months to rob the battery.
Disconnect, don't disconnect, it won't matter much for a few hours.

Mine has no parasitic drains and everything is on switches and my CO monitor is AA powered. I have kept these same batteries from 4 previous campers and they are still going strong.

I almost always and only charge through MPPT and solar. I even have a disconnect from the vehicle alternator and rarely use the convertor/ charger.
 

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