Tips and Tricks
Electrical Adapter-bility
DeMaris

Not long ago we arrived at a small town RV park where shore power connections were at a premium. Every other site had an electrical box--and users were somehow expected to share. Our next-door neighbor was already "tied into" the box closest to our site, and on popping open the cover we found he was already using the single 30-amp outlet. With our 30-amp three-prong male plug looking dead into the face of a 50-amp four-hole female receptacle, it looked as though we needed a quick brush up on 'electrical biology.'

Boondockers that we are, we simply cranked up the wind turbine tower and drew what juice we needed from the West Texas winds. After our neighbor moved along, we plugged into the freed up 30-amp receptacle. While we're fairly adaptable, the experience did jog our thinking: Not everyone has "alternative" power available. Being adaptable may mean the need to carry the appropriate electrical adapters.

The typical RV electric cord is equipped with a 30 amp male plug, identified by three prongs, one of them like a large, round pin, the other two, flat blades in a kind of "V" formation. Higher end rigs, which may chew up a lot of power, may be equipped with a 50-amp plug, having the single round pin, and three flat blades. It doesn't take long to find out if your plug is incompatible with the available park "electrics."

Happily, there are solutions to most of the "odd coupling" problems that face RVers. The most typical that we've encountered is that of an old park equipped with only the 15-amp receptacle that looks all the world like the ones occupying your living room wall. Adapters here vary, from a simple plastic affair that plugs directly into the 15-amp outlet, with your 30-amp shore power cable plugging directly into it. Others are "pigtail" affairs, which have a single 15-amp plug, sprouting a 6" or so chunk of cable, connecting to a 30-amp receptacle. If the connecting cable isn't round, but flat, they may be referred to as "dogbones," by their appearance.

We've found the pigtail or dogbone styles to be more useful connectors. At times we've found a park receptacle to be installed "upside down," and with the simple "block" style adapter, the 30-amp shore power plug is then upside down, tending to fall out of the fitting.

The problem here is that 30-amp shore power cords are heavy affairs, and they tend to drag down heavily on the lightweight construction of the 15-amp receptacle. Worse, when they do tear loose, they may leave pieces of your adapter still attached to the receptacle, an untidy (and at times) unsafe affair.

Similar dogbones and pigtails can be had to connect a 50 amp shore power cord to a 30-amp park receptacle. While all of this is great on the surface, remember, "There ain't no such thing as a free lunch."

Remember the old saw, "The chain is only as strong as its weakest link"? That's also true, electrically speaking. The weakest link in the electrical chain is likely to be the outlet in the park electrical box. For example, if you roll up with your 30-amp equipped RV, and use your dogbone to attach to a 15-amp "standard" outlet, don't count on operating your air conditioning unit. Yes, you may be able to fire it up and actually run it for a while, but running the typical RV air conditioner on a 15 amp circuit will tax things to the limit. In all likelihood, the contacts of the park's service receptacle will begin to heat up, and may burn out entirely. This can lead (once again) to an untidy--and definitely--unsafe affair.

All this means you'll need to live within the limits of the "means" of the electrical service you're attached to. For boondockers, accustomed to the limits of battery storage, this may not be a problem. If you're not used to "counting the cost" however, things can add up quickly. Your RV refrigerator, hooked up to shore power, draws almost 3 amps. That electrical converter that takes shore power and transforms it into something your 12-volt lighting system can use, uses nearly 6 amps when "fully loaded." Now flip on the color TV, the satellite receiver, and the computer, and soon, it can put you right over the edge.

If in doubt, add up the current draw of all your "goodies." If the manufacturer's plate doesn't show amps, but instead, watts, use this calculation: Amps equals watts divided by volts. Here's an example: Our roof air conditioner draws 1,920 watts. 1,920 watts divided by 120 volts equals 16 amps--already exceeding the limits of a 15-amp circuit. Add up all the amps you might use at once, and then start figuring what you want to use when you're not running the air.

Not to mention the fudge factor. While most shore-power electrical consumers are rated at 120 volts, you'll often find park power supplies are notoriously "short," particularly on hot summer days when there's a high demand for power. For example, our 1920 watt air conditioner consumes 16 amps when 120 volts are available. But let's say the reality is only 110 volts are available. 1920 watts divided by 110 volts equals a demand of 17.45 amps--nearly an amp and a half more!

When sitting in this situation, you'll need to make some decisions. If you want to "nuke" your meal in the microwave, it may mean you'll need to turn off other electrical users for the duration of meal-making. It's a matter of trade-offs, but hey, at least you can still eat!