farm | food | videos | price | information | history

672172View
0m 0sLenght
889Rating

On August 17th 1993, the Ives Dairy Substation in Miami, Florida experienced a total system failure. It started when a power surge on the Miami grid fried one of the capacitor banks and caused a breaker to trip open. Unfortunately, the breaker malfunctioned and created an arc fault (a continuous lightning bolt that acted like an uncontrollable welding torch from hell) between the hot side of the breaker and wherever it could find a ground to complete the circuit, thus pulling far more current then the facility was designed for. Unknown to FPL operators at the time, the emergency response system that would have notified the grid dispatcher of a serious problem (who would have then cut the power to the substation and neighborhood to kill the arc fault) was inoperative, and no message was ever sent. Since the dispatcher had no way of knowing about the arc fault, the substation continued to self-destruct. The uncontrolled arc fault caused the coolant (mineral oil) inside the primary transformer to overheat to critical levels until it was boiling in a highly flammable state. This boiling caused pressure to rise inside the transformer (like a pressure cooker) until the seals finally blew. Mineral oil vapor proceeded to pour out at that point (the plume of white fog at the end) which ignited on the arc fault. The flames caused by this immediately ignited back to the source, (the boiling transformer tank), which ignited the mother load of oil inside, causing the substation to explode in a giant ball of fire. The sudden loss of all transformer coolant resulted in a simultaneous flash-meltdown of the transformers innards, which immediately caused the main high voltage fuse to overload and blow (the loud explosion at the end), finally killing the arc. As a side note, even though it sounds like a million things went wrong, there were really only two main things that went wrong. Arcing is actually very common when a breaker opens since the breaker has hundreds of thousands of volts running through it. And capacitor bank failures are common since they can fry in the event of a power surge. The UNCOMMON event that caused this was the fact that the arc-fault suppression system (the system that extinguishes the arc), and the Emergency Response System (that would have told the grid dispatcher that something was STILL wrong) were both placed on the same circuit breaker, and that breaker was faulty. Those two backup systems are really the only final thing a substation has in order to prevent this from happening in your neighborhood, and both of them were inoperative in this instance because of that bad circuit breaker, (and the fact that someone put both the backup system and the auxiliary backup system on the same circuit to begin with - a big no no). You can view an aerial photo of the substation location here: https://www.google.com/maps/@25.9674199,-80.1829731,86m/data=!3m1!1e3?hl=en (Note: this is a current map photo of the newly rebuilt, slimmed down substation that sits where the old substation used to be.)