HPE7-A01 · Question #119
Drag and Drop Question Match each PoE power class to Its corresponding 802.3 standard. (Options may he used more than once or not at all) Answer:
The correct answer is 802.3af; 802.3at; 802.3bt; 802.3bt. PoE Power Classes and 802.3 Standards The four positions most likely represent PoE Types 1–4, which are the device classification tiers defined across the PoE standard evolution. --- The Correct Arrangement | Position (Type) | Standard | Max PSE Power | |---|---|---| | Type 1 | 8
Question
Drag and Drop Question Match each PoE power class to Its corresponding 802.3 standard. (Options may he used more than once or not at all) Answer:
Exhibit
Answer Area
Drag items
Correct arrangement
- 802.3af
- 802.3at
- 802.3bt
- 802.3bt
Explanation
PoE Power Classes and 802.3 Standards
The four positions most likely represent PoE Types 1–4, which are the device classification tiers defined across the PoE standard evolution.
The Correct Arrangement
| Position (Type) | Standard | Max PSE Power |
|---|---|---|
| Type 1 | 802.3af | 15.4 W |
| Type 2 | 802.3at | 30 W |
| Type 3 | 802.3bt | 60 W |
| Type 4 | 802.3bt | 90 W |
Why Each Placement is Correct
Position 1 → 802.3af The original PoE standard (2003). Covers Type 1 devices and Classes 0–3. Max 15.4 W at the switch port, ~12.95 W delivered. Used for IP phones, basic cameras.
Position 2 → 802.3at PoE+ (2009). Introduces Type 2 / Class 4. Max 30 W at the port, ~25.5 W delivered. Used for PTZ cameras, dual-band APs.
Position 3 → 802.3bt PoE++ (2018), Type 3. Max 60 W. Uses all 4 wire pairs instead of 2. Used for high-power APs, video conferencing endpoints.
Position 4 → 802.3bt Still 802.3bt - Type 4 is the highest tier within the same standard. Max 90 W. Used for thin clients, laptops, smart displays.
Common Mistakes
- Assuming 802.3bt covers only one power level - it defines both Type 3 (60 W) and Type 4 (90 W), which is why it appears twice.
- Confusing 802.3at with 802.3bt - "at" is PoE+, not PoE++. The "b" in "bt" can help you remember it came later and is bigger.
- Mixing up wattage at the port vs. at the device - standards specify PSE (switch) output; the PD (device) always receives slightly less due to cable loss.
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