battery disconnect switch for winter storage

Jay4868

New member
I have a 2013 RT Agile and my owners manual indicates that I should put the battery disconnect switch in the on position before connecting outside power. Can someone explain why that is necessary and does that mean I should leave the switch on while the van is plugged in for winter storage to keep the batteries charged. As you can tell electricity is not my strong point.

JOe M
 

gte

2008 RS
Joe,
Welcome. Most of us have learned a lot about electricity since buying an RV. According to my manual the coach power switch must be on before plugging into shore power so the batteries will be charged. I am not certain why but assume it has to do with powering the inverter/charger we have in the Roadtrek units on first and possibly the isolator. Once it is powered the charger can then supply DC to the batteries. Some folks who leave their RVs plugged in all the time probably do leave the coach power switch on, however, once the batteries are fully charged it would not be necessary. That said I do not believe there is any problem if you do leave it turned on. There is probably some parasitic drain on the batteries when the switch is turned off so you would probably want to turn the charging on periodically anyway. Only experience with your unit will let you know how to manage the battery charging.
 

obgraham

New member
Jay, GTE is right on the money. Most (though not all!) of the newer RT's use an "inverter-charger". In this device when you turn off the battery switch, it shuts down the charging function, and there is no pass-through of 110 power to the coach's systems. So you need to flip the switch ON before plugging in.

If you store the rig plugged in, the same applies. The coach batteries will not be topped up if the switch is off. Now if you have the solar charger, and it's sunny enough, that will keep the batteries topped off even if the switch is OFF. It's just the way these rigs are wired.

I'm fortunate to have a storage building in my back yard, with a 30amp outlet. What I do is flip the breaker and battery switches on for 24 hours every couple of weeks. I just don't like leaving the rig plugged in for months on end.
 

BayMarine

Electron herder
What I do is flip the breaker and battery switches on for 24 hours every couple of weeks.
Good idea. A lot of the very newest chargers (but not inverter/chargers that I know of) will go into a "suspend" mode when they've been on float for a long time, and pop back on now and then. They'll also go into a 30 minute or hour bulk (full charge) mode once a week if the battery's been idle. Not that your system needs to do this, but the idea is that coming off charge for a while and then getting exercised is a pretty good way to treat the battery. Assuming the battery doesn't get too low . . .
 

Trekker

Trekker
Good idea. A lot of the very newest chargers (but not inverter/chargers that I know of) will go into a "suspend" mode when they've been on float for a long time, and pop back on now and then. They'll also go into a 30 minute or hour bulk (full charge) mode once a week if the battery's been idle. Not that your system needs to do this, but the idea is that coming off charge for a while and then getting exercised is a pretty good way to treat the battery. Assuming the battery doesn't get too low . . .
Correct, the latest generation of chargers do have a 'suspend' mode. I just put a new ProMariner into my boat. However, for clarity, the inverter/chargers in our RVs are not that sophisticated, and do not have the long term 'suspend' mode. (I can not speak for EVERY unit out there, so there may be exceptions). So leaving it on long term will continue to trickle charge the battery at 'float' level, which would not be healthy for the batteries. Additionally, leaving charger on 'permanently' risks a fire hazard when you might not be there. A few years back a neighbor's car burned up in his driveway while connected to a charger. :cry:

The reason the battery switch needs to be in the 'on' position prior to plugging into shore power is to power up the transfer relay that switches the RV from 12 volt to 120 volt. If the switch is not 'on' the relay will not transfer the circuitry to 120. Notice that there is a large placard in the Roadtrek that indicates that battery switch must be on prior to connecting to shore power.
 
OK. I've had my RV for 70+k miles now, and I still don't understand the terminology. First off, assume dry camping, engine and generator off, no shore power. Above the sliding door, there is a panel which allows me to turn on the house batteries so that I have 12 volt for the lights.
https://drive.google.com/file/d/0B3G0IdRS4Bm0bzR0RnRaelFWNGM/view?usp=sharing

When the rocker switch (on the far right off the pane) labeled battery is depressed to the "on" position, I always assumed the circuit was completed and thus, I had power. And I do. If depressed to the "off" position, I don't have power. Is this the battery disconnect switch? Have they reversed the labels - the "on" label means the battery disconnect switch is really off, allowing the circuit to be complete? If so, do I need to flip my switch (what I see on the panel) to the "off" when I plug in to shore power?:thinking: I don't think I've ever done that in all this time.

The only battery problem I had was when the alternator Y cable went bad and the chassis and house batteries weren't charging while driving.........I turn the battery panel switch to the "on" position the minute I get in, before I start driving, leave it on while camping (battery, generator or shore), and only turn it off when I'm finally home (where I don't plug in).

Any and all input welcome.
 
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gregmchugh

New member
The battery switch on the Roadtrek status panel controls the battery disconnect relay and it works as you described. It has two momentary positions labeled ON and OFF to connect the house batteries to the loads (ON) and to disconnect the house batteries from the loads (OFF) when you are not using the van and do not want the batteries to be discharged by the loads that are always present such as the propane and CO detectors.

The battery switch has no effect on the transfer switch which is used to select which 120v source is active when both the shore power and Onan generator are on. It also controls the delay in connecting the 120v power to the loads to allow the generator to stabilize before being connected to large loads such as the air conditioner. Once the transfer switch has engaged then 12v power is supplied by either a converter on older vans or an inverter/charger on newer vans. On some newer models the inverter must be turned on to charge batteries and supply 12v power.

The label that indicates that the battery switch should be ON before plugging into shore power in order for the batteries to be charged is something that can be explained for some van configurations and is not easy to understand for other van configurations. I follow the instruction but I suspect it may not actually be valid in our 08 RS Adventurous unless the van is not wired as shown in the owner's manual. I have never taken the time to test to see if it is valid. In any case, it is simple to follow the instruction even if it may not really be needed. I very rarely disconnect the batteries in any case since I keep the van plugged in at home.
 

gte

2008 RS
When the switch on the far right is turned on, i.e., the lights come on, you indeed have 12 volt power for your lights, refrigerator, generator start, etc. This switch must be on before you plug into shore power if you want the coach batteries to charge. Otherwise it does not have to be on when on shore power. I leave my switch on when on shore power just to be certain the batteries charge and so I do not need to remember to turn it back on when I disconnect from shore power.
The other electrical switch on the panel for the inverter I leave off all the time unless I want to watch TV when not connected to shore power or I want to charge some portable device while traveling.
 

obgraham

New member
It is indeed one of the mysteries of the RV world why we have a switch labeled "battery disconnect" so we can debate whether it is on or off.

I've relabeled mine: it now says "Battery ON" and "Battery OFF". Much simpler!
 

smokestack

New member
I have a 2016 RT CS. It has 460 miles on it. I keep it stored inside at 40F with shore power connected. After about a week it will not start...chassis battery dead or close to dead. I leave the keys on the floor out of the ignition.
Should I be toggling the battery disconnect switch on the far left above the door. I was under the assumption the inverter/charger keeps the chassis battery topped off via this connection.

I did a load test on the chassis battery under the floor using a battery load tester. It tested good.

Not sure what I am doing wrong and hate to leave it sit at the dealer for a week.

thanks for a recommendation.
 

obgraham

New member
Something ain't right. The chassis battery should maintain its charge for months regardless of the house batteries. However, in my 2014 CS shore power does not maintain the chassis battery.

Something's draining that chassis battery. Either a parasite load, or a wiring error.
 

icarus

Active member
You really should install a positive battery disconnect switch on the house batteries. The isolation relay draws nearly 1/2 amp 24/7. Leaving the rig for more than a few days will prematurely kill the house batteries. The trip lite inverter is not a good fit to leave on to trickle charge the house batteries, it tends to over charge IMHO. A small solar panel or a tiny trickle charger, one for the house one for the engine is the best solution.

As for the engine battery dying after a few days, look for a phantom load, like the radio or security system. A small load over a long time will kill a battery just as dead as a large load over a short time.

Quite simply, pulling the ground cable behind the throttle pedal is a very easy solution.

Icarus
 

gregmchugh

New member
I have a 2016 RT CS. It has 460 miles on it. I keep it stored inside at 40F with shore power connected. After about a week it will not start...chassis battery dead or close to dead. I leave the keys on the floor out of the ignition.
Should I be toggling the battery disconnect switch on the far left above the door. I was under the assumption the inverter/charger keeps the chassis battery topped off via this connection.

I did a load test on the chassis battery under the floor using a battery load tester. It tested good.

Not sure what I am doing wrong and hate to leave it sit at the dealer for a week.

thanks for a recommendation.
Do you have AGM batteries, how many? or Do have Ecotrek lithium batteries?

Do you have the engine generator option or the Onan generator?

Do you have the old style Tripp-Lite inverter under the driver's seat or the newer inverter under the bed?

Is there a battery separator on the firewall under the hood?
 

smokestack

New member
Do you have AGM batteries, how many? or Do have Ecotrek lithium batteries?

Do you have the engine generator option or the Onan generator?

Do you have the old style Tripp-Lite inverter under the driver's seat or the newer inverter under the bed?

Is there a battery separator on the firewall under the hood?

Hi Greg...4 AGMs- two underhood two under-rear
Engine generator
Inverter under bed left
Battery Separator-not sure. Audible clicking when batt switch is cycled.
 

gregmchugh

New member
Do you have AGM batteries, how many? or Do have Ecotrek lithium batteries?

Do you have the engine generator option or the Onan generator?

Do you have the old style Tripp-Lite inverter under the driver's seat or the newer inverter under the bed?

Is there a battery separator on the firewall under the hood?

Hi Greg...4 AGMs- two underhood two under-rear
Engine generator
Inverter under bed left
Battery Separator-not sure. Audible clicking when batt switch is cycled.
In your configuration there may be no battery seperator since the engine generator charges the batteries while driving. I am not sure but there may be no charging of the chassis battery from shore power in your configuration. As you probably already know, with the new style inverters you typically need the inverter turned on to get battery charging while in shore power. The clicking you hear when the battery switch is cycled is the battery disconnect relay not a battery seperator which would be under the hood.

I think in your configuration there is, as already suggested, likely a parasitic drain on the chassis battery that may not be related to the house side electrical system. With the house batteries disconnected using the battery switch and with the inverter off there should be no loads on the house batteries.

If you are not a member already, consider joining the Roadtrek Owners Group on Facebook, a lot of owners there with all the different model Roadtreks helping each other.
 

rapper

New member
Smoke - i am almost sure you have a battery separator. Mine is under the hood, passenger side. It is clearly marked battery separator. Mine is Model 1315-200. This model does two-way charging. http://www.cooperindustries.com/con...sources/instructions/BUS_CBT_INST_180126a.pdf

Did you also turned ON your inverter when plugged in? When turned ON and detects shore power, it becomes a "charger". When your battery separator detects that your house batteries is already at cut-off voltage which is 13.2V and chassis battery voltage is less than 13.2V, it activates the relay so it "joins" the two. This will now charge your chassis battery. It "isolates' the two batteries again when both are above cutoff voltage.
 

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icarus

Active member
^ I believe this battery separator draws about 1/2 amp, while not much, is enough to kill. The house batteries in a few days! (.5 A *24 is 12 ah*7 days is 91 ah. a pair of GC2 batteries has a ah capacity of ~220 ah, so after a week the battery will be drawn nearly 50%, hence the need for a postive off switch on the battery. The door switch just turns the battery off the loads in the van.)

Icarus

PS a better alternative is a BlueSea mag latch relay that draws no stand by current.
 

gregmchugh

New member
I believe you will find that on vans with the engine generator option Roadtrek does not have a battery separator installed and there is no charging of the chassis starting battery from the RV side when you are plugged into shore power. There is no need for the battery separator since the coach batteries are charged from the engine generator not the chassis alternator when the engine is running. Roadtrek could install something to allow shore power charging of the chassis starting battery but they don't do that.
 

CyBeth

2015 CS Adventurous
Greg is correct. I asked the same question on the Roadtreking FB pages and with an RT tech yesterday and got a definitive answer that
- no separator on the CS configured as above
- chassis battery is only charged by engine alternator when engine is running
- use an external charger connected to the jumper points underhood if charging chassis battery is needed
- both "Battery Off" switch AND inverter need to be on for shore power to charge the house batteries
 

Trekker

Trekker
^ I believe this battery separator draws about 1/2 amp, while not much, is enough to kill. The house batteries in a few days! (.5 A *24 is 12 ah*7 days is 91 ah. a pair of GC2 batteries has a ah capacity of ~220 ah, so after a week the battery will be drawn nearly 50%, hence the need for a postive off switch on the battery. The door switch just turns the battery off the loads in the van.)

Icarus

PS a better alternative is a BlueSea mag latch relay that draws no stand by current.
You have correctly raised this point before. Wouldn't pulling the ground connection on the separator accomplish the same thing? Just as easy as turning a switch on and off, and one doesn't need to install another component.?? :thinking:
 

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