Amp, RV service – AC (alternating current) service in modern RVs are rated at either 30 amps or 50 amps. The ampere is unit of measure of electrical current. A 30 amp service provides 12ov power to the camper through through a three wire power cord – black is hot, white is neutral and green is ground. A four wire cord is used for 50 amp service – Black and red are hot, white is neutral, and green is ground. The two hot wires supply two separate 120v legs in the RV. If the service is wired properly, the two hot wires are of different electrical phases and can be connected to supply 240 volt service.
 30 amp receptacle |
 30 amp plug |
 50 amp recepticle |
 50 amp plug |
Amp hour (Ah)– an ampere hour is the amount of charge in a battery that will allow one amp of current to flow for an hour. A milliampere hour (mAh) is 1,000th of an amp hour. It is commonly used as a measure of charge in portable electronics batteries, such as a laptop computer or notebook, and provides an indication of how long it can operate without needing to be recharged. A battery’s amp hour rating has little significance unless qualified by the design discharge period. Cold cranking amps and reserve capacity ratings provide better information for battery selection.
Anode rod – a sacrificial rod used mainly in metal hot water heaters. When dissimilar metals and water combine an electrochemical process called galvanic corrosion occurs. In this process one metal corrodes preferentially to another when both metals are in electrical contact and immersed in an electrolyte (the water in the heater). Galvanic rods are made of metal alloys that have a more active potential than the metal that would otherwise corrode, so the anode material is corroded – sacrificed – instead.3
3Wikipedia – Galvanic Corrosion, Galvanic Anode
