Used power generators come in all sizes. From small portable ones to large industrial ones, the purpose of all generators is the same, to provide electricity. How much electricity you need for a generator to give out is what determines the size of the generator. Generators give out electricity by running mostly a diesel engine coupled with an alternator. The Alternator is what provides the electricity. The diesel engine is directly proportional to the size of the alternator. Thus you have huge engines running in some of the large generators. There are some small generators that run on gas.

In used power generators what you have to see is how many hours it has been used before. Some have meters for it and some don’t. The overall condition should be good and if the engine or the alternator has been rebuilt, how long has it run since its overhaul, and what condition it is in.