Quick way to run 12-110 volt inverter in Scamp 13.

[zack sc]

I have a Scamp 13 that was built in 2015, and as far as I can tell there’s no cigarettes style 12 volt port anywhere inside the Scamp. I’m in California and wanting to be able to run a small air purifier, 50 W, for a half an hour or so. I already have an inverter I use in my tow vehicle, and I’m thinking If I can just connect up to 12 V power in my Scamp , then I can plug the air purifier into that. So I guess my question is: what’s the easiest way to tap into 12 V power inside the Scamp with all windows and the door shut.? I have a wire pair with clips on one end and a cigarette style 12 volt port on the other end, and I guess I could just connect that onto the power going to a lightbulb, but I imagine there’s a better way that I could still do quickly. Any suggestions and advice are welcome.

[zack sc]

Here are my notes from looking at my DC system before. I’m guessing that third slot, the 20 amp one, is for the domestic fridge which I almost never run on DC, so maybe I could use that power? If so, what is the best and quick easy way to tap into that?
DC power.
——
20 A. Bedroom corner light
20 A. 3 lights, 2 Kitchen and 1 shower
20 A
15 A

[steve dunham]

I cut a 12VDC cigarette type HD receptacle into the face of the side dinette bench in our Scamp . Ran the wire from the receptacle to the converter and put it on a separate fuse .

[zack sc]

Thanks very much Steve. Can you explain more about where you lead the wire and how you connected to the converter? Where is the converter? How do you connect to it?

Also, I’m a little confused as to why are you say converter, That is, why is there a converter involved?
because I think I’m getting the Power From a 12 V battery, the one at the front of the scamp, and I’m just finding a way to get the 12 V power to my inverter that will boost it up to 110 V AC.

[gordon2]

Id bet you have a converter and a separate power distribution center (PDC) with fuses and breakers. And I would also bet there are a number of unused fuse slots. After disconnecting battery and all power you can remove the PDC to access the back side of it. There Id bet you will find a common negative buss bar and places to connect the positive wires to one side of the fuses. Dont confuse either with the 120 AC side! Run white 12 g wire from the common buss to the new outlet neg side and black 12 g wire from an unused fuse slot on the fused side, to the outlet positive. Add a fuse rated at 10 amps or 110% of the rating of the outlet, whichever is less.

Once you get into it you can see how the other 12 volt circuits are wired. The PDC has a max rating for each fuse slot and for the total power used but the above is within the specs if we have the same PDC.

SEE THIS: https://www.progressivedyn.com/wp-co...onnections.pdf

Disclaimer.. I am not a licensed electrician and do not instruct you to follow my guide. I'm just telling you how I did it. You are fully responsible for what you do. I am not.

[steve dunham]

Originally Posted by zack sc

Thanks very much Steve. Can you explain more about where you lead the wire and how you connected to the converter? Where is the converter? How do you connect to it?

Also, I’m a little confused as to why are you say converter, That is, why is there a converter involved?
because I think I’m getting the Power From a 12 V battery, the one at the front of the scamp, and I’m just finding a way to get the 12 V power to my inverter that will boost it up to 110 V AC.

The converter contains the breakers for the 120 VAC in your trailer , it also supplies 12 VDC to your trailer for the interior lights , water pump , furnace and refrigerator plus it charges your trailer battery
My Scamp converter had some spare fused DC outputs and I used one of the spares to power the 12 VDC receptacle

A converter changes AC to DC
An inverter changes DC to AC
We plugged our 150 watt inverter into the 12VDC receptacle
I put the 12VDC receptacle on a separate circuit because I did not want to overload one of the existing 12VDC circuits
I ran a pair of #12 AWG wires ( Red / Black ) from the converter to the receptacle- fused at 15 amps

[gordon2]

Originally Posted by steve dunham

The converter contains the breakers for the 120 VAC in your trailer , it also supplies 12 VDC to your trailer for the interior lights , water pump , furnace and refrigerator plus it charges your trailer battery..

Be careful with that assumption. His Scamp was built the same year as mine.
In mine, the converter and the breaker / fuse panel are separate units. A photo from the OP would clear it up.

By the way, I suggest white wire for ground (neg) and black for positive instead of black and red, because the rest of the camper is wired with the white and black method... no need to confuse things with different colors for the same thing in the same camper.

[gordon2]

By the way.. you did say quickly but Steve and I suggested the best way to do it.. even if its not quick. I doubt the air purifier will do much good, considering how not air tight the Scamp is. But if you want to try and breath easier tonight in Cali, then I have two ideas...

1. Just use the clips to attach the inverter to the battery and run an extension cord into the camper through a window, and use tape to seal up the cracked open window.

2. Find a light fixture with wire nuts inside the cabinet if you can, or some other place where the wiring to the light is easy to work with. With all power off and battery disconnected, Disconnect or cut the wires and connect the hot wires to the cigarette lighter outlet. Then use the plug for the inverter.

Again, this is a temp solution and I am not responsible for what you do or what happens when you do it.

[steve dunham]

Originally Posted by gordon2

Be careful with that assumption. His Scamp was built the same year as mine.
In mine, the converter and the breaker / fuse panel are separate units. A photo from the OP would clear it up.

By the way, I suggest white wire for ground (neg) and black for positive instead of black and red, because the rest of the camper is wired with the white and black method... no need to confuse things with different colors for the same thing in the same camper.

Thanks Gordon , I was not aware of that change , all the Scamps that I’ve seen
had a converter .
I had a spool of 12- 2 cable with one black and one red conductor so I used it to feed the 12 V receptacle but your correct , to maintain continuity black and white may be better

[gordon2]

Originally Posted by steve dunham

...I was not aware of that change , all the Scamps that I’ve seen had a converter...

There is still a converter of course.. its just a separate unit. I dont know how common this arrangement is compared to the integrated converter/panel (single box). The separate converter / power panel is a nice solution since you can replace the converter easier and I assume for less cost. But it does create one problem as implemented with Eveland's product.. the converter has a standard NEMA plug, which goes into an outlet on the power panel. And it has a tendency to fall out, stopping the converter from working. Judging by how many people complain that they battery dies and then find the converter unplugged, I must assume that this is a a common converter / panel arrangement in Scamps.

[zack sc]

Thanks a lot Steve and Gordon. This is amazingly helpful. Deeply appreciated and I am really getting an education here.
I think what I may do is :
1) cut the cord on my Belkin 300W "Sine Power Inverter" and crimp a pair of 15 or 30 amp Anderson Powerpole connectors onto that.
2) Use a 16, 14 or 12 AWG wire pair to connect my Belkin inverter to 12 volt power either behind the converter, or up in a cabinet at the back of the Scamp where there are some easily accessible wire nuts, going to a light.* (see post 2 below for details)

It turns out the air purifier (a small TaoTronics) only draws 7 watts, so I figure that is means my Belkin inverter should be only drawing about 0.6 amps from my 12 volt battery. That seems pretty manageable.

I am thinking that the Scamp is pretty well sealed except for the louver vents for the fridge and the hot water heater. I'll try to tape up the hot water one that I am not using, but I guess I need to leave both the upper and lower vents open near the fridge if I am using the dometic fridge on propane. (What is that upper one for anyway?)

[zack sc]

This shows the vents on the side.

[zack sc]

* What I meant to say is, once I have Anderson connectors on the 12 volt power wire of my inverter, then I can make a wire pair with Andersons on one end and a few mm of bare stripped wire on the other to connect to other things without dealing with the cigarette lighter. Not sure what AWG wire I have around, but definitely 16 awg, probably 14, maybe some 12? But I am thinking at this low power draw (7 watts) maybe 14 or 16 awg may be okay? I can try to limit the length a bit. What do you think?

[zack sc]

Can I tape over that upper vent if I am using the fridge on propane but not using the stove? Is the lower all that the fridge needs, or does it need both to be open?

[Civilguy]

Originally Posted by zack sc

Can I tape over that upper vent if I am using the fridge on propane but not using the stove? Is the lower all that the fridge needs, or does it need both to be open?

Zack, unfortunately, you need both vents on your refrigerator. One draws air in at the bottom and the other releases it at the top along with excess heat from the absorption process. This is important to maintain the refrigerator's cooling.

[steve dunham]

Originally Posted by zack sc

* What I meant to say is, once I have Anderson connectors on the 12 volt power wire of my inverter, then I can make a wire pair with Andersons on one end and a few mm of bare stripped wire on the other to connect to other things without dealing with the cigarette lighter. Not sure what AWG wire I have around, but definitely 16 awg, probably 14, maybe some 12? But I am thinking at this low power draw (7 watts) maybe 14 or 16 awg may be okay? I can try to limit the length a bit. What do you think?

Sizing a conductor is not based on ampacity alone - mechanical strength is also part of the picture . If you plan on hooking wires directly to the battery , there should be a fuse in the run as close as possible to the battery

[gordon2]

Enough time has now passed that I am no longer going to address the QUICK methods and instead focus on the better or best options.

A cigarette lighter style outlet is more versatile in that you can use it with phone chargers, volt meters, even your inverter if the load is low enough, etc. The ones I have seen are "rated" at 10 amps but with the cheapness I have seen, I would be wary of using more than 7 or 8. And you can make or buy a cigarette lighter style outlet with PowerPole connector, as seen in the below photo.

The 30 amp Anderson PowerPole is a better option than a cigarette lighter style outlet for 7 or 8 amps up to 30. So even if you only plan to use one or two amps, the Anderson PowerPoles will give you more flexibility in the future, especially with the inverter. That is assuming you wire it right for the higher currents, and that means no 16 or 14 gauge wire! Use either 12 or 10 and fuse appropriately.

I use both. The cigarette lighter style outlet is wired to the fuse panel. My PowerPole outlet is on the front bench were the 10 gauge wires from the battery enter the camper. The battery wiring is 30 amp fused AT the battery (of course) and then connects to a common ground buss and a common positive buss under the bench (an upgrade from Scamp wiring). The PowerPole outlet connects to the buss's with 10 gauge. With this arrangement I can easily draw 25 amps for my Amateur Radio on high (100 watt) RF output.

Another option is to connect the PowerPole outlet to the main fuse panel as described above for the cigarette lighter style outlet, but I think you will find that there is a limit to 20 amps for any single fused circuit. Thats still plenty for your current needs.

Above disclaimers still apply. I am not responsible for the consequences of your mods.

[Tony D]

Keep in mind that inverters are not very efficient. Does the housing gets hot? The heat is wasted electrical power. I’d guess your air purifier and inverter together are pulling around an amp.

[zack sc]

Thanks Tony. I see somewhat vague claims that the Bestek 300 watt pure sine wave inverter that I have is 80 or 90% efficient. Does that seem believable?

I measured the 110 volt power coming out of the inverter to be 3.1 watts, with a smart plug. If the inverter is 80 percent efficient that would imply about 4 watts dc and about 0.3 or 0.4 amps at 12 volts. But I am a little concerned that maybe the inverter is much less efficient than they say, and that the current may be closer to 1 Amp as you suggest. Thoughts?

[zack sc]

( Looking back at my earlier posts I see that I overestimated the PowerDraw of the small air purifier. But I am still very concerned about efficiency and the difference between 0.4 and 1 amp draw at 12 volts.