Do electrical transformers protect the surrounding wires from power surges?

If a power surge from a house shot back towards a transformer, would it ground the charge or bypass the transformer and harm the surrounding wires?Do electrical transformers protect the surrounding wires from power surges?Actually Davies, a little of both would occur. To understand this you need to understand how a transformer works. Take one that operates a small model train set for example. One end plugs into an outlet where it receives 120 volts AC. The wire from the outlet goes inside the transformer case and wraps around a piece of iron called a core. It might wrap around it 10,000 times. Then another wire is wrapped around the same core, but maybe only 1,000 times. In this case, the second wire would receive 1/10th the voltage of the first, so the output would be 12 volts AC. If the train set needed DC power, it would be run through something called a rectifier after going through the transformer.



The important thing to remember is the wires running from the outlet do not ever come in contact with the wires going to the train tracks. Transformers only work with AC power, each time the electricity cycles (60 times per second in the US.), a magnetic field is formed around the core by the first wire. The field is then picked up by the second wire and fed out to the train. Surges, such as from lightning, or short circuits in some wiring, are almost always DC, the powe surges dramatically in one direction for a microsecond. Since the transformer isn't designed to transmit DC power across the core, and the two wire wraps are not physically connected, the transformer acts as a resistor and traps most of the surge on the incoming side. The only exception to this is if a surge is large enough, it can heat up the wire wraps around the coil and melt some of the insulation, allowing a physical connection to occur between the two coils. In this case, the transformer is usually destroyed, but at least some of the surge energy is used up in destroying the transformer, so what travels out the other side is diminished to a large degree.



Most surge arrestors you buy for household use have a small coil inside, along with some capacitors and other devices to help absorb some of the surges that might come in from an electrical line, they are taking advantage of a transformers ability to do what it does. The ones that hang on the power pole near your home are no different, they are just larger and much much heavier. They are not designed specifically to absorb surges, but they still have an ability to do so just by their nature.



So to answer your question directly, if a surge did shoot back from a house to a transformer, what is most likely to be damaged is the transformer, or the wires leading from the house to it. The ones on the other side of the transformer would be partially protected. You might notice the wires on the other side of the transformer from your home are smaller than the ones leading to your house. This is because they run at a much higher voltage, and therefore carry less current. In my experience what damages these smaller higher voltage wires is trees, rodents and lightning. Wiring that gets damaged on the home side is generally caused by a wiring fault at the home or meter box. Hope this helps, take care, RudydooDo electrical transformers protect the surrounding wires from power surges?No, the transformer itself wouldn't ground it. I don't know if they have some kind of surge protector, by the transformer would just 'pass it on' (most likely blow a fuse if the trannie survived