Electrical Control and Distribution

The products recommended within these pages are intended to be used with our book on creating your own minivan camper conversion, but can be used by anyone.

Rather than provide product links, we are choosing to make recommendations for what you will need, and provide brand and model numbers where specifics are necessary. We may bring product links back after we have time to find sources for everything.

Ground Fault Circuit Interrupters

A ground fault circuit interrupter’s sole purpose is to detect an imbalance in the load between the “hot” side of an electrical line and the neutral side. The slightest difference (usually about 1/3000ths of an amp) is all that it takes to trip these detectors, and to keep you safe from accidental shock. They should be used anytime that you are on a concrete surface, bare ground, or even within reach of a grounded surface (like kitchens and bathrooms).

There are many different styles on the market, with the most common type being a GFCI receptacle, now required in kitchens and bathrooms within 6 feet of a water line or faucet, and in garages, basements, or even outside. Around swimming pools a GFCI will usually be in the form of a circuit breaker with a little white “trip” button on it for testing.

But for construction sites and RV’s they also come in a “portable” version that is simply a short cord or device with a plug on it and a receptacle in which to plug your device or extension cords.

A very small, compact unit that works great for a single cord or device is the TRC ShockShield GFCI portable plug (part #90265-6-012). However, for a compact unit in which you can plug three cords, and also has a standard cord and plug on it (which takes up less room around the receptacle that you are plugging into), we would recommend a Morris Tri-tap portable GFCI (Part # 89006). There are many brands made by many manufacturers, but as long as they look like these, almost any of them will do the job for you.  If you go to Google and click on the “Shopping” link at the top of the page, and then search portable GFCI, you will probably see several devices, most of which would work for your minivan camper conversion or for any RV or camping use.  

Extension Cords

Extension cords are one of those “dime a dozen” products.  Everybody’s got one, of one kind or another.  But for your minivan camper conversion, we recommend flat cords, rather than the round ones. Why? Because flat cords will fit through a door opening better, and you can usually close the door completely without doing any damage, either to the door seal or the cord. Always check your door visually though to make sure there’s enough room for it. If your door is out of alignment, it could pinch the cord too tight, and ruin the cord, as well as “energize” the body of the vehicle or cut the cord and short it out.  That’s why you need the GFCI mentioned above.

Because there are so many extensions cords on the market, I am only going to give you the parameters to look for in buying your cords. I recommend having one 25-foot cord and TWO 50-foot cords. For most camp sites the 25-footer will be enough to reach a park power post, but just in case you get farther from the power post, having a couple of extra cords that are longer will come in very handy. For your cords used for hookup to the park’s power, you want:

  • a flat cord

  • 12-gauge wire

  • rated for outdoor use

  • 15-amp plug and socket(s) (can be triple tap if you desire)

As long as the cords meet those requirements, they will work. The reason you want one rated for outdoor use is because they could be laying in the hot sun all day, and if they aren’t rated for outside, the UV rays will eventually damage the insulation on the cord. The reason I suggest 12-gauge rather than 14-gauge, is because you get less voltage drop, and also the heavier the wire, the thicker the insulation on it, and it’s good to have the extra protection, especially for outside use.

For inside the van, an indoor cord will work, and you can even use a smaller cord, since you won’t have as far to go, and won’t have to  worry about a drop in power. One cord should be enough, although I would definitely recommend one with a triple-tap socket, in case you need to plug in more than one appliance. You’ll want:

  • a flat OR round cord

  • 14-gauge wire for 15 amp loads, 16-gauge wire for 10-amp loads ( I recommend 14 gauge)

  • can be rated for indoor OR outdoor use

  • 15-amp plug and sockets (preferably a triple-tap head)

Surge Protected Power Strip

This is the device you will plug into your extension cord from the park’s power post to your minivan camper conversion. It is the same device so prevalent today on computer equipment. Some come with a push-button circuit breaker, and sometimes a switch to turn it off, and that’s OK, but not necessary. A surge protector protects your equipment from voltage spikes in the electric line.  You may go years and never have a problem, but if you do, it can protect your sensitive equipment from damage.  When they react to a spike in voltage, they simply burn out.  There is nothing to reset, so don’t bother looking for it.  If you find one that doesn’t work, and you’re sure there’s power to it, then it has probably done it’s job and needs to be replaced. It wouldn’t hurt to carry a spare.

This device should be placed somewhere behind the driver’s seat, where it’s easy to get to. It will be your main source for 120 volt power within the van. If you have the appliance cabinet that we recommend, it can be attached to the rear inside of the cubby-hole for the coffee maker, unless you see a better spot for it. If the device doesn’t have mounting feet on it, then you can secure it with a couple of plastic wire ties. Just make sure you position them so they aren’t over the receptacle holes.

Battery Charger

As my book states, you don’t want a battery charger any larger than 15 amps for this application, because it will be plugged into the cigarette lighter socket, which is probably fused at 15 amps. You don’t want to blow the fuse by trying to put too much through it.  And for the things you will normally use with your van, you aren’t likely to be drawing any more than this from the battery when parked.  As long as you put as much or more into the battery than what you draw out of it, you’ll be fine, and should never run your battery down. If you have to use an inverter for 120-volt power, try to plug it into your battery pack, which we will discuss next.

Some battery chargers may come with a cigarette lighter plug on them already, but don’t get a charger that is too small. Try to stay as close to 15 amps as you can without going over. If what you find had battery clips on it, you can cut those off and have a cigarette lighter plug wired onto it. Just make sure that the hot wire (usually the red one) goes to the center tip of the socket, and the ground (usually the black wire) goes to the outer shield. If in doubt TEST IT with a meter before plugging it into your system or you could cause some damage!

This battery charger should be placed on the floor in the driver’s area when you are parked and have 120-volt shore power available. This serves as the same device as the “converter” that you see on larger RV’s, except that you won’t need all the extra circuits that they provide, and for our purpose there is no reason to “hard-wire” anything in.

Battery “Jumper” Packs

These handy devices have only been around for a few years, but I don’t why people didn’t think of them sooner. On larger RV’s you usually have a secondary battery, to run your lights and things without running your engine battery down. When you turn off your ignition, a relay disconnects the secondary battery from the vehicles charging system. When you start your vehicle, it reconnects to the system to recharge the batteries.

For our “light duty” use in our minivan camper conversion, we can usually get by with a smaller battery, and one of these portable battery packs will work just fine!  Rather than being composed of lead and acid, as most vehicle batteries, these new units use a type of dry-cell battery, so you don’t have to worry about knocking them over or emitting hydrogen fumes when charging. Most will come with jumper cables already attached, in case you DO run your vehicle battery down, but hopefully you will never have to use it for that. Most of them have at least one 12-volt socket on them, so you can plug any of your 12-volt devices into this battery instead of your vehicle socket. That way, if you run this one down, you can still start your vehicle.

They come in several different “amp” sizes, but you don’t want to get one too small. For normal use, where you have shore power most of the time, in intermediate size would be fine. But if you plan on going longer without power, then you may want one with more amps so that it will last longer.

So how do you recharge these units?  All you have to do is run a 12-volt cord between the 12-volt power socket on it and your vehicle socket. This will require a special cord with a male plug on both ends, but they are commercially available. If you can’t find one, you can buy the parts at any electronics or auto store and make your own. Any time you start the vehicle to go somewhere, just plug the secondary battery pack into the vehicle and you have the same type of setup that the bigger RV’s have, except that where theirs switch automatically, you have to manually unplug it when you park, and plug it in when you head out.

Some of these battery packs come with all kinds of extra stuff, from lights to air compressors.  Although having those things for emergency use is nice, they don’t have anything to do with the basic use, but if you want them, and can afford the extra toys, go for it.

Inverters

Inverters do one thing, they convert your vehicle’s 12-volt DC (direct current) power into 120-volt AC (alternating current) power for use by normal household appliances and tools. The one thing you have to be careful of is overloading them. Inverters are rated by the wattage being used on the outgoing (120-volt) side.  The problem is that they can draw nearly ten times that on the DC side, according to Ohm’s law.  And by that law, wattage divided by voltage equals amps. So if a 120 watt appliance on 120 volts draws one amp, then a 120 watt appliance on 12 volts is going to draw 10 amps!  This is why you will only see inverters of 200 watts or lower with 12-volt plugs on them.  Anything larger than that and you HAVE to connect it straight to the battery of the vehicle!

With that in mind, be mindful of how you use these inverters and never try to plug anything heavier into them than what they were designed for. Even though they are protected by fuses or circuit breakers, you could do damage to them. ALWAYS check the wattage or amperage rating of the appliance you are going to plug into them. If it’s rated in amps, then multiply the amps times the voltage to get the watts, so you can compare them. A 200 watt inverter that plugs into a cigarette lighter socket CAN NOT handle any more than 1-2/3rds amps! They are only designed for small things like a shaver, computer, or small electronics items. If you need to have 120-volt power for anything larger than that, then save it for a land line or get a much larger inverter that connects straight to your battery! And then make sure your vehicle is running when you use it!  Remember, whatever you use in amps or watts on the 120 volt side is going to be ten times that much on the DC side, and you can drain a battery very quickly! That’s why heavy-duty inverters should only be used for short periods of time. They aren’t meant to take the place of household power, like for running an air conditioner constantly!

Also, here’s another thing to consider. Inverters come in two types. One is a “modified sine wave” inverter, which means that even though it has taken the clean DC power and caused it to alternate between negative and positive 60 times a second, it may not be a “true” sine wave. It could be a square wave, a saw-toothed shaped wave, or anything in between.  They will work on “most” things, but some electronics are sensitive to the type of wave they use, and could be damaged!  For that reason, we only recommend a “true” or “pure” sine wave inverter, in which the electrical alternating wave is nicely rounded as it makes its path from positive to negative.  This type of inverter costs a little bit more, but the power output is exactly as you would get at home from the power company. If you have sensitive electronic equipment, like a TV, or sound system, you don’t want to take chances with damaging it. Spend the extra money to get a “true” sine wave inverter and protect your equipment! 

12-volt Extension Cord

This is one of those “optional” things that may not be necessary if your van already has 12-volt sockets in the rear somewhere. Our van doesn’t, and if we want to run our portable 12-volt cooler in the back (or anything else) we would have to run a 12-volt extension cord from the front socket. Usually these cords come in 12-15 foot lengths, have a male plug on one end and a female socket on the other, and are readily available at any electronics or automotive store. But don’t buy the cheapest one you can find. I just read a review of one of these cheap ones and two different people reported that the wire gauge in it was too light, and they had problems with it from losing too much voltage! Not only that, but they can get hot if they aren’t heavy enough!  So always ask what the wire gauge is.  The wire should be at least 16-gauge, and preferably 14-gauge.

Summary…

There are a lot of other devices available that would fall in to this category, but the items mentioned above are really all you need to get power into your minivan camper conversion.  If you are boon-docking without power, then obviously you won’t have a park’s power post to plug into, so you may need to “create” some power. That would fall under the category of electrical “generation“, and will include generators as well as solar panels.