What actaully protects an amplifier?

[chipper]

I am very curious because when i was playing some music in my car one of my wires from my subs came off and shorted my amp and the amp kept on trying to play music every 1 or 2 seconds and yellow protection LED would blink every two seconds or so. so i turned of the radio to stop it quick and my amp still plays fine even when turned up full volume so no harm done. Anyways my question is whats actaully protection my Kicker ZR240? i see two boxes (K1) right channel and (K2) left channel. What are those boxes for? are those part of what protects the amplifiers outputs?

Thanks in advace!

[Perry Babin]

Generally over-current protection monitors the voltage across a resistor. When sufficient (excessive) current flows through the resistor, the voltage across the resistor reaches the threshold point and that triggers either an op-amp or a transistor which can shut down the amp, open relays or shut down the drive circuit for a channel.

The boxes are relays. Relays generally close after a short mute delay and open when the amp is switched off or when the protection circuit is engaged.