PSA Airlines Canadair Regional Jet Systems (PSA-CRJ) Practice Exam

What is the time limit to establish A/C power after selecting the Battery Master on?

1. 3 minutes

2. 5 minutes

3. 10 minutes

4. 15 minutes

The correct answer is: 5 minutes

Setting the Battery Master switch "on" activates the aircraft's electrical systems, but it also brings with it the responsibility to establish external power or start the APU (Auxiliary Power Unit) within a certain timeframe. The time limit to establish AC power after selecting the Battery Master switch on is crucial to maintaining battery health and ensuring that the onboard systems operate efficiently. If power is not established within five minutes, the aircraft’s battery can become overly depleted, potentially impairing its ability to support essential systems. This limit is a standard practice in aviation to prevent battery over-discharge and subsequent malfunctions in systems that rely on electrical power. The other time limits mentioned in the options—three, ten, or fifteen minutes—do not align with the operational protocols set forth in training and manuals for the PSA Airlines Canadair Regional Jet. Hence, five minutes represents the critical window for establishing AC power after the Battery Master is activated.