The Inverter

This is the final article in the series on the Roadtrek electric system. The inverter is the fourth out of four power sources in the Roadtrek - at least in Roadtreks that are not the new ETrek which brings in solar and other electric sources as standard and options.

I have kept the inverter for last because it is the most technical and complex system to understand. The best part is that you do not need to understand it to use it. It's use is simple. You simply turn on the Battery switch and then turn on the Inverter switch which is located on one of the walls in your Roadtrek - mine is next to the side entrance door and you immediately have 110/120 volt power in several of the outlets of your Roadtrek.That is providing you have charge in your batteries. Because the inverter takes the DC (direct current) 12 volt power in your coach battery or batteries and changes it to 110/120 volt AC (alternating current) power.

I will briefly talk about some of the technical things about the Inverter later but for the moment, here is what you need to look for to get your inverter started.

The Battery Switch is on the right. When you press it it will turn on and the LED to the left of the switch will  light.

DO THIS FIRST!

There is the INVERTER Switch on the top. It is a simple toggle switch. Push the top and it is ON. Push the bottom of the switch and it is OFF. 

(By the way - the switch below is the outside porch light.)

DO THIS NEXT!

THAT IS IT!

Some Roadtreks depending on Model and Year will have these switches in different locations!

It does not get any simpler than this - but what have you got. You are going to say, "Hey! This outlet does not work!" Well, not all of the outlets will work when you are using the inverter. Roadtrek has only connected a few outlets in your Roadtrek to the inverter. The inverter draws a lot of power from the batteries or battery and you will find yourself in the dark quickly if you were to try to run everything electric in the Roadtrek all at once and also the inverter only supplies 750 watts of power - we will get into this more later - and that is not enough to run the air conditioner, the microwave, or something like a hair drier (the typical hair dryer needs 1500 watts). It is plenty to run the TV, the home entertainment unit with DVD, a laptop computer, charge a cell phone or two, and any small electric like an electric razor. It should be enough to run a small coffee maker. The more you use, the faster the batteries will run down. So if you want to go along for awhile you need to be conservative in what you plug in.

So where are those outlets that will work. They seem, from what I am told, to vary from model to model and year to year. There will be about three of four outlets total that will have power. The TV outlet will have power and this outlet powers the home entertainment center also. I also have an outlet in the front of my Roadtrek behind the driver's seat that is powered and also the outlet on the wall above the kitchen counter to the left of the sink. One thing that we noticed (actually, Meryl noticed) is that all of the outlets that we have that work on the inverter have a sign next to them.

The TV/Home Entertainment Center outlet located in the cabinet on the passenger side over the bed. I added that switch and three way adapter cube - you will not have one. See the sign again behind.

The same outlet behind the driver's seat. Roadtreks offer a coffee maker as an option, and I believe this is where it would plug in as when we saw one it was located in this area.

The outlet over the kitchen counter top and sink.  There is the sign again!

As I said, there are not more outlets because your 750 watts is very limited - plus at the same time you are using your batteries (or battery - I have two coach batteries standard - some Roadtreks only have one) you are powering your 12 volt lights, your water pump, your hot water heater, your overhead fan, and maybe your furnace.

I have not put my inverter to an endurance test but we have gone for three hours on the inverter watching TV, using the laptop, and charging cell phones with the 12 volt system also working and have not put any real drain on the batteries. I am sure we could go longer. Eventually though you will have to recharge your batteries - either by driving, running the generator, or plugging in. 

Now, let's get a little more technical. The inverter in the newer Roadtreks (not the ETrek) since about 2005 have a Tripp-Lite 3-way Inverter/Converter/Charger. I am not an engineer. What I know about this I have read from others who purport to know far more than I about these things. This unit does three things. It inverts 12 volt power to 110/120 volt power - this is what is enabling you to watch TV and run your laptop when the inverter is "on". It charges your coach batteries when you are driving and it charges your coach batteries and engine battery when you are plugged into shore power or are running your generator. The converter part gets most confusing and basically what it does is change 110/120 volt power - like shore power - into 12 volt DC power - as in what runs the lights, water pump, hot water heater, etc. I am not going to go any further into the converter part because frankly, I don't understand it beyond what I have explained. If you read the "NOTES" that are attached to the Roadtrek Electric Simulator it was revised again in December 2012 and goes into explanations of the Converter on the Tripp-Lite.

The actual inverter unit is inside your Roadtrek and its location varies. There are various settings on the inverter unit. I have never touched the settings on mine. It was set to "AUTO/REMOTE" at the factory and that is how I have left it. There is also a DC OFF setting and  a CHARGE only setting. The AUTO/REMOTE Setting lets the unit do everything that you need it to do and operate when you want the inverter to make 110/120 volt power from the batteries when you push the switch (the remote part) in the coach. 

There are also LED indicator lights on the inverter unit that will give you information about what the inverter is doing and various conditions that it may be in. 

There is also a RESET on the unit that you need to be aware of. Here is what the manual says - 

Resetting Your Inverter/Charger to Restore AC Power

Your Inverter/Charger may cease supplying AC power or DC charging power in order to protect itself from overload or to protect your electrical system. To restore normal functioning:
Overload Reset: Switch operating mode switch to “OFF” and remove some of the connected electrical load (ie: turn off some of the AC devices drawing power which may have caused the overload of the unit). Wait one minute, then switch operating mode switch back to either
“AUTO/REMOTE” or “CHARGE ONLY.”

By the way, here is a link to the manual.

The other thing you need to be aware of about the Tripp-Lite is that if you replace your coach batteries to a different type of battery - wet cell, gel, AGM - you need to change the setting on the Tripp-Lite unit by moving dip switches. There is a chart in the manual about how to do this and it is easy to do. You only need to do this if you install a different type of battery. If you replace X with X you do not need to do this. 

There are other dip switches for other settings. I would not attempt to change anything here unless you seriously understand what it is all about. I strongly believe - learned the hard way - to leave well enough alone.

The manual has a troubleshooting guide in the back. 

Now, one more thing to know about the Inverter. It has a fan and that fan sometimes makes noise. It is a low hum that is barely noticeable but if you notice it you will wonder what the heck is making that noise. The fan does not only come on when using the Inverter to get power in the outlets but also if the Roadtrek is plugged into shore power or running the generator (and the unit is charging the batteries). When I heard this noise I asked the service center on my next visit and they assured me that it is perfectly normal - and to ignore it. So I ignore it. It has never bothered us or kept us awake at night. It is barely audible. The other part is that it does not always run - which is also normal. If you don't hear it - that is fine. If you do - that is fine, too!

Added April 2013:
 
Lastly, the Tripp Lite inverter/charger that Roadtrek installs has two other functions. It has a surge protector rated at 450 joules and also a UPS (Uninterrupted Power Supply) function. These are engaged when you turn the Inverter Wall Switch ON - and if you turn the Inverter Wall Switch ON when plugged into 110v shore power - an outside 110 volt power outlet that you plug the Roadtrek's power cord into, you will have 450 joules of surge protection for your electronics and also if there is a power drop in voltage outside coming in, the inverter unit will continue to power, for example, your television through inverted battery power until the outside power stabilizes.  So this happens when you are both plugged in and put the Inverter Wall Switch ON at the same time. <><><> Will this take the place of a Surge Guard surge/power protection unit? Roadtrek says yes. I use the Surge Guard (or Progressive Industries surge/power unit if that is what you have) in addition. For one thing, 450 joules is a low rating for surge protection. My other thought is this. If a surge protector is tripped due to a lightening strike, etc. generally, the surge protection unit is no longer usable. It must be replaced completely or have its circuit replaced on units where that is even possible (Progressive Industries units can have their circuit replaced if it blows due to a power surge). Tripp Lite does not state what happens to the inverter/charger unit if it has a power surge go through it. I would not want to be in a position after a strike to have to replace or repair the Tripp Lite inverter/charger. I would rather replace the portable Surge Guard which in a strike would not let the surge enter the electric power cord of the Roadtrek. The choice is yours. If I am in error, I will error on the side of safety.