what does battery disconnect switch not disconnect?

CHICKDOE · 07-24-2016, 09:07 PM

we have a 2015 forest river cardinal model 3825 but this is a more generic question. our trailer has a battery disconnect switch installed and i was told to always turn it off (or is it on, the termonolgy confuses me) whenever i have the trailer in storage. i was told this will save the batteries. but i also know that we have the lippert level up system installed and 5 slide outs (two electric and three hydraulic) and i know these will all work off battery power when the battery is 'disconnected'. so this has got me wondering, just what does the battery disconnect switch actually disconect? my guess is that it disconnects the feed from the battery to the circuit breakers / fuses. now if only the lippert system and slide outs are still connected to the batteries how much of a drain will those put on the batteries in storage? the slide outs seem to be controlled by switches that are normally off (open) so they shouldn't put any load on the battery. the lippert system does have a control panel that you can power on or off via a button on the panel. but even to do that there has to be some level of current flowing to the panel just to sense the on / off button. do my assumptions seem reasonable? can anyboy think of anything else that is on even if the battery disconnect switch is activated? if just seems that the batteries are draining faster than i woud expect even though they are disconnected? would physically removing the battery cable from the battery be beneficial? would it hurt any of the systems that expect constant battery power available? thanks

bubbles · 07-25-2016, 08:19 AM

I believe the O2 sensor is still powered and if you have an electric awning it will still be powered through the control switch. If you have electric steps they also will be powered for extension via the door switch. There may be other systems in your unit and you are correct in that if a system is still powered but requires a switch action it will not put a drain on the battery (same as an open circuit).

**Flybob** · 07-25-2016, 08:44 AM

There is not right answer to this question as some units are wired differently. The controller for the leveling system may use some power if it has a remote. The CO/Propane sensor is almost always on as well as a small draw in the Radio/DVD player. The parasitic draw of these items will kill the battery over a few weeks if not aux charging ( solar or battery tender) are available. If you absolutely can't have a source of charging, you can add a second battery disconnect or move the one you have so it covers everything. If you need a quick fix until you can make the change, you can disconnect the negative Battery terminal. If you have access to shore power, I like the battery tender solution. It saves wear and tear on the converter and battery and works well. If you leave plugged in and use the converter, bake sure you regualrly check the electrolyte levels in the battery.

ShermanD · 07-25-2016, 09:12 AM

the battery disconnect switch should shut the cabin fuse block, so anything that those fuses control will be shut down. In our Sunseeker MH the fuse block is located below the Battery shut down switch in the entrance stairwell next to the battery box.

I have no idea where your cabin battery box is but that doesn't make any difference. Open the battery box and see how many wires come off of the main positive terminal, One one should go to the battery shut down switch and the rest will have in-line fuses in them somewhere. You can most likely see them if you look under the trailer near the battery box. What ever those fuses control, will still be hot when the cabin battery switch is shut down.

You will have to determine that yourself because those were all added on after the main cabin fabricated.

It seems as though you have already found out that the slide outs are not on the switch. The only real way to find out what else is not switched on your unit is to pull those inline fuses one at a time and see what they control.

While your at it, make yourself a wiring diagram. because acquiring one from Forest River is like trying to pull a wisdom tooth with a piece of cheap thread, IT AINT GONNA HAPPEN

rockfordroo · 07-25-2016, 09:16 AM

USUALLY the only things left powered are things that have their own switches that are either off or on (such as the power jack, slides, the light on the front of the trailer to help with hookup if you have one). The idea is to disconnect parasitic loads that you can't control as well (Propane/CO detector, furnace brains, fridge brains, etc.).

WolfWhistle · 07-25-2016, 12:49 PM

Are you on shore power?
WW

Telstar · 07-25-2016, 12:49 PM

The battery disconnect on our Cardinal does not disconnect CO2 sensor, jacks and the light near the front jacks control.

awellis3 · 07-25-2016, 01:58 PM

Quote:

Originally Posted by CHICKDOE

can anyboy think of anything else that is on even if the battery disconnect switch is activated?

Yes. On my Rockwood the wardrobe slide's control module is always "on" and fused separately. This is because there must be power going to the slide motors to keep the slide in. There is a separate circuit going to the control panel switch to make the slide go in and out. That is through the fuse panel. The hot-all-the-time to the control module is not affected by the battery cut off switch and will be a constant draw. Enough to cause a small spark when you disconnect the ground wire at the battery.

camaraderie · 07-25-2016, 04:03 PM

The solution is simple...put a REAL battery disconnect switch on the negative battery post and make sure all negative connections run there. 7 bucks at Walmart.
Fully charged batteries will retain at least 1/2 their charge for at least 90 days if all loads are removed. Of course the other simple method is to remove the negative ground wire each time...but the disconnect is easier.

BandJCarm · 07-25-2016, 04:06 PM

The terminology certainly confuses me too. Many say everything does. LOL

I just mentally disregard the word "disconnect". So, it's Battery On, or Battery Off.

Least that helps me.

milvet33 · 07-25-2016, 05:01 PM

This may be of help

When to use the battery disconnect switch in your RV | Mobility RV Service

robbdrell · 07-25-2016, 05:02 PM

What about one of those small solar battery chargers you attach to your battery? Anyone ever use one?

tomrob1161 · 07-25-2016, 05:29 PM

on our Rockwood 8315 BSS, TT, everything is disconnected, Inc. CO2 detector & radio, except tongue jack and slideouts.

CHICKDOE · 07-25-2016, 05:37 PM

thanks for all the replies. you've more than confirmed what I had been thinking. my batteries are draining too fast while the trailer is in storage and the batteries are 'disconnected'. from all the posts I can think of several loads that do not get disconnected: propane sensor, jack control unit, possibly the inverter (it has a remote switch which needs power), possibly the audio system (again a remote), and then there is remote that works with the slides. so i'm thinking a battery disconnect terminal attached to the battery to physically remove the cable connection is the way to go. if I do this I suspect the batteries should hold charge for a month. I go to the storage lot at the start of each month the run and exercise the generator so I can reconnect the batteries at that time and recharge them. as it is now I have to jump start the generator each month as the batteries have lost charge and are not able to start the generator. i'm really wondering what the manufacturer was thinking when they took the effort to include the battery disconnect switch that doesn't really disconnect all of the battery load. why bother? it seems all it is is an on/off switch to control 12 volt power into the 12 volt fuse box. if this is all it is why not just put it next to the fuse box and call it what it is, fuse master power in switch? and this is not just limited to the manufacturer. I can state that more than one dealer has a misperception about this switch also!

Retired JSO · 07-25-2016, 06:01 PM

Quote:

Originally Posted by CHICKDOE

thanks for all the replies. you've more than confirmed what I had been thinking. my batteries are draining too fast while the trailer is in storage and the batteries are 'disconnected'. from all the posts I can think of several loads that do not get disconnected: propane sensor, jack control unit, possibly the inverter (it has a remote switch which needs power), possibly the audio system (again a remote), and then there is remote that works with the slides. so i'm thinking a battery disconnect terminal attached to the battery to physically remove the cable connection is the way to go. if I do this I suspect the batteries should hold charge for a month. I go to the storage lot at the start of each month the run and exercise the generator so I can reconnect the batteries at that time and recharge them. as it is now I have to jump start the generator each month as the batteries have lost charge and are not able to start the generator. i'm really wondering what the manufacturer was thinking when they took the effort to include the battery disconnect switch that doesn't really disconnect all of the battery load. why bother? it seems all it is is an on/off switch to control 12 volt power into the 12 volt fuse box. if this is all it is why not just put it next to the fuse box and call it what it is, fuse master power in switch? and this is not just limited to the manufacturer. I can state that more than one dealer has a misperception about this switch also!

If you remove the ground wire from the batteries, there will be nothing that can draw from said battery. Using a disconnect, I still juice to my jack but everything else is dead.

Telstar · 07-25-2016, 06:13 PM

The slides on our Cardinal are hydraulic, the pump is connected direct to the buss, not through the disconnect switch.

milvet33 · 07-25-2016, 07:28 PM

I'm far from an expert on the disconnect switch however, I can tell you that I accidentally switched mine off and I was hooked to shore power and after two weeks my coach batteries and my engine battery were all dead! Couldn't be any worse if I just left it on without shore power. I always leave mine on and plugged into shore power.

WolfWhistle · 07-26-2016, 03:14 PM

a small solar panel and controller would be a huge benefit for you, if the trailer isn't under trees or inside (obviously). Plus have you thought about how long you have to run a generator to fully charge a battery or batteries? again, solar is ideal for this purpose.
WW

CHICKDOE · 07-27-2016, 04:00 PM

to all, just thought I would give an update. I spent the morning trying to find everything that will run even when the battery is 'disconnected' via the factory installed disconnect switch. here's what I found that I believe are always on and drawing battery current:

level up leveling system (this has an always on control panel)
the slides that are hydraulically actuated (these have an always on sensor that works with a wireless remote)
propane detector

then there are several lights that will operate with the batteries 'disconnected' but they should not be drawing current as they are controlled by individual on/off switches. of course if you left one on by mistake it would draw power while disconnected.

so yes, my batteries do have a load on them and get drained even when 'disconnected'.

metalsideup · 07-28-2016, 10:57 AM

It is fairly easy to reroute factory wiring in order to attain a true battery disconnect. The disconnect switch consists of two large threaded lugs onto which the factory wiring are attached via ring terminals. If one reroutes the factory wiring so only one wire comes from the battery (or battery bank) to a disconnect switch lug, and all other wires going to the RV's systems are connected to the other battery disconnect switch lug, a total battery disconnect is achieved. This is true if no other wires come out of the battery bank other than the ground-to-frame wire and the wire to the disconnect switch.
As noted, installing a ground terminal disconnect or disconnecting the negative cable at the battery terminal achieves the same thing.
Batteries so isolated from all RV loads will still experience a slow "self discharge" as a matter of physics simply by sitting there minding their own business.
If one achieves a total battery disconnect and then plugs in to shore power, the converter will not have any path to charge the batteries, but most will still provide 12vdc to power the RV's 12v systems.

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