PoE uses ___ for powering low voltage lighting sources and controls them using pulse-width modulated signals over the same Ethernet cable.

Prepare for the Independent Electrical Contractors (IEC) Year 4 Exam. Access flashcards, multiple choice questions, and detailed explanations. Enhance your readiness and achieve your certification!

Multiple Choice

PoE uses ___ for powering low voltage lighting sources and controls them using pulse-width modulated signals over the same Ethernet cable.

Explanation:
PoE supplies DC power over the Ethernet cable to powered devices, typically at around 48 V DC. The lighting driver then uses pulse-width modulation on that DC supply to control brightness by varying the on-time of the power to the LEDs, effectively changing the average output without wasting energy. All of this occurs over the same cable that carries data, combining power and control in one link. AC power isn’t used in PoE for these low-voltage lighting applications, wireless connections aren’t involved, and it’s not a mix of AC and DC. So the missing term is DC voltage.

PoE supplies DC power over the Ethernet cable to powered devices, typically at around 48 V DC. The lighting driver then uses pulse-width modulation on that DC supply to control brightness by varying the on-time of the power to the LEDs, effectively changing the average output without wasting energy. All of this occurs over the same cable that carries data, combining power and control in one link. AC power isn’t used in PoE for these low-voltage lighting applications, wireless connections aren’t involved, and it’s not a mix of AC and DC. So the missing term is DC voltage.

More Multiple Choice Questions
Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy