By Jack Bradshaw – Reprinted from Winter 2006 Motorcader
Another year has gone by and what fun we had traveled with each of you. While traveling, we have encountered many problems with electrical power in campgrounds. I hope the following information will help clear up some of your concerns. Having bad power is often worse than having no power at all. Poor quality power can create many problems with the performance and longevity of your appliances. Since electricity isn’t something that you can see, hear or touch, dealing with campground power gremlins usually requires a little knowledge.
Let’s look at some of the problems you may encounter:
Overloads: An overload condition exists if the total amps of all appliances being used simultaneously exceed the current capacity of the campground breaker. Invariably, this leads to tripped circuit breakers when attempting to operate too many appliances.
The best solution is to familiarize yourself beforehand with how much current each appliance consumes. Most AC appliances list the number of watts they consume: so dividing the watts by the voltage you can approximately determine the current requirements in amps. When setting up in the campground you should let your wife know which power you use, either the 30 or 50 amp service, so both of you know how much power is available to manage.
Under/Over-voltage: Improper supply voltage is responsible for most campground problems. Excessive voltage is most damaging to lights, absorption type refrigerators, and other devices equipped with heating elements. Low voltage is I hardest on appliances equipped with ac-motors such as air conditioners, fans, compressor-type refrigerators, and icemakers. Most AC appliances are designed to operate at a nominal II7 I volts, plus or minus 10 percent. Thus, whenever the electrical supply drops below 105 volts or rises above 130 volts, damage to your coach could happen.
Voltage Transients: Transients (sometimes called surges or spikes) are momentary increases in the AC supply voltage. They are caused by lightning, switching large electrical loads on and off, or by a fault within the utility company’s AC power grid. This can expose your coach’s appliances to thousands of volts, causing significant damage. Since you rarely have any advance warning of the presence of transients, it’s usually a good idea to have some form of surge protection.
Polarity Problems: In a correctly wired 120-volt AC shore power circuit, with a 30-amp plug, the line (black) conductor is hot: the neutral (white) and ground (green) wires have little or no voltage with respect to earth ground. With your 50-amp service, you have two lines that are hot.
What you can do to prevent damage to your coach:
In order to measure AC voltage, you should have an accurate digital (DMM) volt-ohm (VOM) multi-meter. The AC voltage at a campsite power outlet should always be measured before you plug your coach into it. The power cord prongs should be clean and shiny; any plug or wiring that is frayed, split or otherwise damaged should be replaced.
Many campgrounds have ground-fault circuit interrupters (GFCI) installed at the power outlet. Your coach has a GFCI receptacle in the bathroom that protects against any grounded circuits. They are designed to reduce shock hazards by automatically tripping power whenever a leakage in current is detected. The GFCI does this by comparing the current flowing to a load with the current returning from it.
A little preventive measure to protect your coach will give you many happy days of seeing our beautiful country trouble-free. So now that 2006 is here, let’s sign up for the motorcades and get going for another exciting year in your great FORETRAVEL.
I hope this has cleared up another question about your coach.