The transformer is the microwave component which increases the voltage of the alternating current of the oven, this may be referred to as ‘stepping up’ the voltage. The type of transformer used in microwave ovens is a very powerful component and should not be touched. Transformers usually consist of two wire coils wrapped around a core, called primary and secondary windings.
This final main microwave oven component is usually constructed of a material called Mica. This is where microwaves enter the unit having been produced by the magnetron we discussed in Part 1. The cover stops food residue and grease from affecting the vital components of the oven, which may become clogged and overheat without the protection of the cover. Sometimes this cover needs replacing, though it is rare. Replacement may be necessary of the cover becomes damaged or begins to spark. It can also become less rigid over time, and cut to fit replacements are readily available.
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