What is a wastegate actuator?

What is a wastegate actuator?
The wastegate actuator sits along side the turbo. Here we have the cold or air side of the turbo and here we have the hot or exhaust side of the turbo.
This is the wastegate actuator.
So when the engine is at high speeds the turbo is at risk of going over speed or over boost the engine.
This is were the wastegate actuator comes in to pay.
So as exhaust gases are fed into the hot side of the turbo from the engine at high speeds it can create a lot of boost pressure. If this get to much, the wastegate actuator is set to open a value on the hot side the turbo diverting excess gasses straight out to the exhaust. Wastegate controller.

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