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I really need more detail on this as to waht you are asking. However, There should be a disconnect box near the unit. It is either a non-fusible or fusible type. If it is the fusible type it should have time delay (refered to as slow blow) fuses in it. This could also be a breaker type disconnect rather than fusible. Some air handler unit also have fuses in the control box on the unit, although most manufacturer's are now using HVACR breakers in the units.