How long to initiate the normal stop cooldown after engaging the PT brake?

• A. 9 minutes
• B. 2 minutes
• C. 15 minutes
• D. 30 minutes

Answer: (A)

Core idea: giving the system a brief period to shed heat and stabilize before moving into the normal stop cooldown.

After the PT brake is engaged, heat and pressures within the brake and associated components can remain elevated. Allowing a short cooldown window lets residual heat dissipate and fluids settle, reducing the risk of thermal shock, warping, or pressure spikes when the cooldown sequence continues. Nine minutes is the specified interval that balances safety with operational readiness, ensuring components reach a safer state without unnecessary delay. Shorter times wouldn’t give enough cooling, while longer times add unnecessary downtime without extra safety benefit.