The Short Circuit Scenario
3. What Happens When DC Meets a Transformer
Now, let's consider what happens when you try to run DC through a transformer. Remember that static magnetic field we talked about? Well, before that even becomes the main problem, another issue crops up. The primary coil of a transformer has very low resistance. When you apply a DC voltage, you're essentially creating a short circuit. This causes a huge surge of current to flow through the coil.
Think of it like this: Imagine trying to force a river through a tiny garden hose. The pressure would build up, and eventually, the hose would burst. Similarly, the excessive current flowing through the transformer coil will generate a lot of heat. This heat can quickly damage the insulation, melt the wires, and ultimately destroy the transformer. Not a pretty sight, or smell!
There's a brief moment when DC is first applied where the magnetic field does change (as it builds up from zero), and a small voltage might be induced in the secondary coil. However, this is a very transient effect. As soon as the magnetic field stabilizes, the induced voltage disappears, and the transformer is left to deal with the massive current overload.
In simple terms, applying DC voltage to a transformer leads to a massive current rush, overheating of the coils, and the potential for catastrophic failure. It's akin to giving a delicate electronic device a massive power surge — it simply cannot handle the load.
