A class 2 transformer is used as a standalone security system. It is used in combination with general purpose power supplies and come in a variety of sizes. The largest class 2 transformer has an output rating of 50 VA.
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A class 2 transformer is a passive electrical device that is used to supply class 2 circuits. These transformers have a maximum volt-ampere rating of less than 100 amperes and a maximum secondary output of thirty VAC.