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This is a simple free program for calculating electrical load for single family residential dwellings. This calculation determines the size of your electric service entrance (and meter) and main electrical panel based upon your potential load usage. If you are thinking about adding on or building a new house, then this calculator will help you to determine if your existing entrance is big enough or if you will have to spend a considerable amount to upgrade. Your local codes department will probably let you use a larger service entrance than the minimum if you want (up to a point), but you can't (and don't want to) have one that is even a little bit too small.
This program calculates total service load based upon the 2005 National Electrical Code Article 220. A balanced load is assumed.
Note: This program makes quick work of a lengthy calculation. In many cases you can use the values for volt-amp nameplate ratings that are provided and you will still get pretty good results (as an estimate only). Also this program does not have any provisions for usage allocation in the case of multiple major appliances circuits, so you will notice that if you input that the dwelling has more than one dryer circuit for example (maybe one in the basement and another in a main floor utility area) then it will show that you need to have a much bigger service entrance, but this isn't really correct in all cases because the code recognizes that you probably don't usually have a dryer plugged into both of them at the same time. If however, you have a second dryer outlet in an area of the house which might be used as a separate habitation the inspector will probably count the extra appliance circuit against the total load, and make you get a bigger entrance, because of the likely potential for simultaneous use - for example if the basement not only has a dryer plug, but also it's own full bath and a kitchenete area, and an exterior entrance. When in doubt, contact your local codes authority before you do anything expensive.