Which cable factors influence PoE performance?

• A. Conductor resistance, gauge, and cable length
• B. Jacket color and shielding
• C. Number of twists per meter
• D. Connector type

Answer: (A)

In PoE, the amount of power that actually reaches the device is governed by the electrical path the power travels through. The key factors are the resistance of that path, which depends on how thick the conductors are (gauge) and how long the cable run is. A longer run or thinner wire increases the total resistance, causing a voltage drop I × R that reduces the voltage available at the powered device and wastes heat through P = I^2 × R. Thick gauges reduce resistance and help deliver power more efficiently, while longer lengths worsen drop and heat if the current is significant. Jacket color or shielding don’t affect the DC power path, and the twists per meter mainly influence high-frequency signaling for data rather than the DC power delivery. Connector type can add only a small contact resistance compared to the overall copper path, so it’s not the primary driver of PoE performance.