What happens to ACMP after the parking brake is engaged for 6 minutes?

When the parking brake is engaged for a duration of 6 minutes, the ACMP (AC Motor Pump) shuts off as a safety precaution. This is an important feature to prevent overheating and possible failure of the pump by ensuring it does not run indefinitely while the aircraft is stationary. The automatic shutdown helps in maintaining the integrity of the hydraulic systems and is designed to activate under specific conditions such as when the parking brake is applied for an extended period.

In essence, the design prioritizes operational safety by limiting the continuous operation of hydraulic pumps when the airplane is not in motion, thereby avoiding potential damage to the hydraulic systems. This aspect of ERJ systems aids in efficient aircraft management and operational reliability.