Wednesday, March 13, 2013

Charging the Roadtrek Batteries

There is a lot of discussion on various forums and readers have asked me about charging the Roadtrek batteries during periods of non-use. Some are interested in attaching trickle chargers to keep the batteries charged. With Roadtreks with the Tripp-Lite three way inverter, all you need to do to charge the all of the batteries fully at the same time and that includes your one or two coach batteries and your vehicle battery. Roadtreks with model years of 2005 and earlier will only be  charging the coach batteries in this way.

This is as simple as plugging the Roadtrek into shore power and you can do this at home. In this article - even though it is simple - I will take you through the steps and show you what is involved in plugging the Roadtrek in.

You will need a few things to do this. You will need a 30 amp socket to 15 amp plug adapter and that looks like this:

This adapter can be purchased at any RV supply store and even Walmart in the RV section of the auto department. You may see this type or you may see just a plug with a socket on one side and a plug on the other. The one shown here is called a dogbone adapter and it is the easiest to disconnect from your power cord because of the handle on the back of the socket. It is worth the few dollars more to buy this type.

If your Roadtrek power cord does not reach the outlet at your house, mine doesn't, you will need an RV extension cord. I have written about this before and it is worth repeating. You want an extension cord that matches the 10 gauge wiring of your Roadtrek cord. Never use a household extension cord. The cord you want will look like this:

This RV extension cord was purchased in Walmart - again in the RV section - for $50 and is 30 feet long. You will find this cord in RV stores also and lengths vary from 25 feet to 50 feet. The socket on this cord lights up when plugged in showing that there is power in the cord. That is nice, but I would rather have a cord with a plug and socket that has pull grips on the back. If your outlet is within reach of your Roadtrek's power cord plug you DO NOT need an extension cord. Just follow the steps leaving the extension cord off.

The other thing that you will need - though it is not absolutely necessary but is a wise thing to use here - is a power/surge protector. Even though I am plugging in at my own outlet on the outside of my own house, I do not trust that there cannot be a power surge coming through the wiring at any time. We have had power surges in the house and we have lost electrical devices that were not surge protected - one nearly resulting in a serious fire - had we not been present when it happened.  Here is my Surge Guard. The choice of Surge Guard or Progressive is yours. Only get the model from either company that monitors and stops the flow of electricity if voltage changes in addition to surge protection. There are portable units and permanently installed units. This is a portable unit and you will find it only in RV supply stores - and some of those do not stock them regularly. Here is my Surge Guard 30 amp unit (your Roadtrek is 30 amp and you want a unit that is also 30 amp):

With these three pieces of equipment, you are ready to begin.

First - go inside your Roadtrek and turn on your battery switch. There is a large sign inside my Roadtrek near that switch that says to turn it on whenever connecting to external power, and that is why I do it. Leave this on through the whole time you are charging and plugged into shore power.

Here is the switch - press and release and the red LED will light showing the switch is ON:

While you are inside at the monitor panel, press and hold the TEST switch on the left in the photo above and see what your Battery Level is:

You see here that my battery is on the second LED from the bottom. When the batteries get to this point you want to charge them. The bottom light indicates that the battery level is LOW - see the "L" and this is not a good thing for the batteries. Some people with older Roadtreks will use a an automotive voltage meter and test the battery directly at the battery posts. This is not easy to do on Roadtreks 2011 (mine) and later. In newer Roadtreks - 190's and 210's in particular (as I do not know the battery location in the Sprinter models), the batteries were changed by Roadtrek from wet cell batteries that require regular maintenance to maintenance-free AGM batteries. With this, Roadtrek discontinued the use of a slide out draw that the batteries sit on in a compartment on the outside of the passenger side of the van and replaced that with an access hatch that no longer slides out. Here is the compartment, closed, on my van - this is in front of the rear passenger side tire:

Here is a view inside with the locking door open so that you can see the two AGM 6 volt batteries connected together. The tray they are sitting on does not move:

Here is a close up view of what you can see of the top of batteries from outside - there is no real room to reach in (and there really does not need to be unless you want to get to the terminals with a volt meter):

OK - this was all just an aside to show you the batteries and why the monitor panel is important. In addition, you should know that in the newer Roadtreks there is no 12 volt outlet socket inside - older Roadtreks did have these. There are places where you could wire one in yourself. I have not. With one you could use a voltmeter that plugs into a 12 volt vehicle outlet.

Now - back to getting all of your batteries charged.

The next step - and really folks, I am going through the steps simplistically just so that what you need to do is clear - is to start plugging everything together.

Simple steps - first you are going to get your Roadtrek power cord out and you will move it from inside the storage compartment though what is called "the mouse hole" and out under your Roadtrek. Here is the mouse hole as seen from inside the outside storage compartment (different models may look different):

Here is the view from outside the compartment where the plug pulls through. You can see here that the plug sits in a capped storage box that keeps the mouse hole closed when the power cord is not in use:


A side note about  the plug in the mouse hole - this plug is not always here when you first get your Roadtrek. Mine was not. It was inside the storage compartment. There are little V fingers that hold this cord in place here. If you pull too hard from the other side the plug will come back through. In the cold weather, it is very hard to move this plug then back through to this side past those fingers. It is much easier to do in the warm weather. Just don't pull it into the storage compartment at the end when you are putting it all away. (In the photo on the left you are seeing the City Water hose connection.)

Here, below, you see the cord pulled through. This is just about all that I need because I am using the extension cord. If you don't need an extension cord you need to pull a lot more cord out until you can get the plug to the outlet.  In the cold, it is not easy to get this cord either in or out of the compartment though the mouse hole. In the warm weather, it is much less of a problem. A trick that Meryl has found is that hand over hand with two hands gets the cord out easily - and again, in the cold, it is still hard. What she does is pull a loop of cord from inside, out through the compartment door, so that the loop is not twisted and then pull - hand over hand - one hand inside and one hand outside at the mouse hole, alternating hands - and the cord comes out. Reverse this to get it back in and it is much easier than just trying to tug it out.

 Now, plug in the power/surge protector into the Roadtrek plug. If you are using an extension cord plug the end of the extension cord into the other end of the protector unit:

Another side note - in the cold and even sometimes when it is warm, the plugs and sockets are difficult to push together. It sometimes takes a lot of effort to get them together with no gap. It is even harder to get them apart. Plugs or sockets with pull handles are easier. There is something that I recently learned about to add to any RV plug or socket to make this easier when pulling them apart and I going to order some and will let you all know all about them when I get them.

Take your extension cord or your Roadtrek power cord plug (if no extension cord, also the protection unit) to your outlet. Your house outlets are generally either 15 amps or 20 amps. I am lucky enough to have a 20 amp outlet in my backyard with nothing else on the circuit except a flood light that I wired permanently into the outlet box. When I connect the Roadtrek here, I turn that flood light switch to off so that the motion sensor does not turn the light on while the Roadtrek is plugged in. With 20 amps I can just about use everything inside the Roadtrek when it is plugged into my house with the exception of running the air conditioner and the microwave at the same time. They can each be run without the other. What would happen if I put them both on at the same time is that I am going to trip a circuit breaker - most likely in my house. See my articles on The Electric System to understand all of this better. When just charging the Roadtrek, any house outlet will do.

Now, take the adapter plug and plug the extension cord large plug into the large socket on the adapter. If you are not using an extension cord, then plug the large plug on the power/surge protector unit into the large socket on the adapter.

Now, for the moment we have all been waiting for - take the small plug on the adapter and plug it in the wall outlet!  Note, that this all has been done in this order so that until this moment, there has been no live electricity running through anything that you have been connecting - and this step is just plugging a regular plug into a regular household outlet, just like you do every day.

The power/surge protection unit had a delay before it sends current through its socket and into your Roadtrek (or any RV). When you plug in the unit you will see a Line Voltage LED light come on but it takes two and a half minutes for the current to be allowed to pass through and out. This is to protect your circuits should the unit shut down power because of a variation of voltage - too low or too high. It automatically turns itself back on then when the voltage is correct but it does not allow the voltage to just push immediately through - and that is why there is this delay. The delay can seem like it takes forever. During the delay an LED flashes next to where it says "Time Delay When Flashing". When the power starts to flow you hear a loud "click" and a green LED  lights showing "POWER ON". Newer units than mine now have a digital readout instead of the LEDs.

That is it! Your Roadtrek batteries are now charging!

How do you know?  Go inside the Roadtrek and push and hold the Test button on the monitor panel and you will see this:

You should see all of the Battery LEDs lit all the way to the "C" on the top. That C indicates "CHARGING". When you are plugged in as you just did (or your generator is running you should see this.

I take the power/surge box and put it under the van just to keep it out of the weather should there be any. All is weather proof and can stay out in the rain. Since I am leaving this plugged in for a length of time it is also (in my neighborhood) better to hide it all under the van out of sight from the nearby street.

How long should you charge your Roadtrek's batteries?  I asked a Roadtrek Service Technician this question and he told me that to fully charge the batteries the Roadtrek needs to be charged for 12 hours. I plug the Roadtrek in during the day and 12 hours later go out and unplug it. Yes, sometimes in the middle of the night and sometimes well after midnight.

When it is time to unplug the Roadtrek do the
 steps in reversing - taking the plug out of the wall outlet first and then disconnect everything and put it all away. As soon as you unplug from the wall outlet go inside the Roadtrek to shut OFF the battery switch, but before you do, push the test button again. This soon after charging you will still see all the LEDs lit up to and including the top green LED at "C". This may even light like this when you test for several hours. I am told that residual electricity in the circuit to the panel keeps the monitor showing "C" when you have the battery switch on and push the test button for a short while after unplugging. So don't be surprised if it still looks like this photo (as it was above). After a short while, if you check the battery level it will be at "G" which is where it should be. Before you leave shut off the battery switch - why waste the charge!

I said it was simple and it is. Why has this article taken so much to say - plug it in. Well, as you have seen, while you could just plug it in, there are a few things to do along with that. And as we went along you had an opportunity to see how everything should look, how the monitor panel will read, what the "mouse hole" is all about, and you got to see what the new battery compartment looks like in the 190 with its two AGM batteries.

I have a schedule set up to charge the Roadtrek in the months that it gets little to no use. The generator is run for its exercise (which also charges all of the batteries) on the 15th of the month and the Roadtrek is plugged in and charged on the 28th. The batteries hold their charge much longer in the warm weather and when the Roadtrek is out on trips every few weeks the batteries stay nicely charged on their own. Every time you plug in at a campground you are charging the batteries. In the winter, however, the level drops in two weeks after the generator's two hour run to what you saw in the photo above of the monitor panel with only the bottom two LEDs lit. After charging, by the 15th usually the panel is lit up to the "G" which is fine.  I had been forgetting to run the generator for its needed monthly exercise and also plugging the Roadtrek in to charge. It is now on my computer and cell phone calendars and I am reminded that day to take care of business.

While I have been writing this, the Roadtrek has been charging on my driveway all day. Now, I am going out (it is 1:30 am) to unplug it - and it is unexpectedly snowing outside... (What else is new?!)


  1. Thank you, thank you, thank you for this! This has helped a ton!

  2. I left my Roadtreck with a friend for 4 weeks and when I returned my battery disconnect switch won't turn on at all and I have no house power at all. I think he may have left some interior lights on and completely discharged the coach battery. How long would I have to drive it for the battery disconnect switch to operate again and ultimately re-charge the coach batteries?

    1. You can try driving for two hours - highway driving - and see if you can then turn on the battery disconnect switch at that point. It will take at least 12 hours of charging plugged into shore power to get the batteries back to where they should be. You are not going to be able to use the wall monitor panel to see where the charge is until you can turn on that switch with enough power in the coach batteries.

  3. Must the power inverter switch be ON in order to charge the batteries from the generator? Thanks

    1. No. The inverter wall switch does not have to be on to charge the batteries. All the inverter wall switch does is put power into the 110 volt wall outlets that are wired to the inverter. This switch is not an ON/OFF stitch for the TrippLite unit but a remote switch for the purpose I just stated. The only on/off switch is on the TrippLite unit itself - the middle position of the slide switch. That slide switch has three positions - Auto/Remote on left, OFF in middle, Charge Only on right. The switch should always be set to Auto/Remote which allows the wall switch to work, and the batteries to charge.