Follow up to 3019131-2015-00005.The phase b fuse failed, leading to the breakdown/electrical fire in the heater controller fuse holder.The 180ohm of residual resistance between the poles of the phase b fuse holder suggest the fuse turned into a 436w heater element at the time of failure.This would provide enough energy to create the damage seen.A current limiting / timing delay fuse has a higher heat capacity that a fast acting fuse.(b)(4) believes that the combination of three factors (power brown outs, pulsing load and thermal isolation) allowed the fuse in question to be repeatedly heated and cooled.This temperature cycling caused the fuse to partially melt internally, creating a 180 ohm bridge measured.This bridging turned the fuse into a heater.With no way to.
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