What is the maximum permissible load on the APU generator in kVA?

What is the maximum permissible load on the APU generator in kVA?

• A. 20 kVA
• B. 40 kVA
• C. 60 kVA
• D. 80 kVA

Answer: (B)

The maximum permissible load on the APU generator is determined by the APU’s own generator rating. For the CRJ-550, the APU generator is rated at 40 kVA, which means that is the highest apparent power it can supply without overloading the APU or causing electrical instability. Staying within this limit ensures stable voltage and prevents overheating or an APU trip. Loads up to 40 kVA keep the aircraft’s essential systems, environmental controls, and avionics powered reliably. Values like 20 kVA are below what’s typically required when multiple systems are in use, while 60 or 80 kVA would exceed the APU’s capability and risk overloading it or triggering protective shutdowns. If more power is needed, you’d bring the main engines online or use external power.

The maximum permissible load on the APU generator is determined by the APU’s own generator rating. For the CRJ-550, the APU generator is rated at 40 kVA, which means that is the highest apparent power it can supply without overloading the APU or causing electrical instability. Staying within this limit ensures stable voltage and prevents overheating or an APU trip.

Loads up to 40 kVA keep the aircraft’s essential systems, environmental controls, and avionics powered reliably. Values like 20 kVA are below what’s typically required when multiple systems are in use, while 60 or 80 kVA would exceed the APU’s capability and risk overloading it or triggering protective shutdowns. If more power is needed, you’d bring the main engines online or use external power.