Public class boundaries used by the tools
| Class | PSE power | Power at PD | Applicable Type |
|---|---|---|---|
| 1 | 4 W | 3.84 W | 1–4 |
| 2 | 7 W | 6.49 W | 1–4 |
| 3 | 15.4 W | 13 W | 1–4 |
| 4 | 30 W | 25.5 W | 2–4 |
| 5 | 45 W | 40 W | 3–4 |
| 6 | 60 W | 51 W | 3–4 |
| 7 | 75 W | 62 W | 4 |
| 8 | 90 W | 71.3 W | 4 |
Type 1 corresponds to the original 802.3af range, Type 2 to 802.3at, and Types 3 and 4 to four-pair-capable 802.3bt. The table is a planning boundary from public Ethernet Alliance material; it is not a reading from the connected port.
Type, Class, and budget answer different questions
- Type identifies the standards generation and supported range.
- Class expresses a power level used during classification and allocation.
- Per-port ceiling tells whether one port can supply the PD.
- Total PoE budget tells whether all simultaneous ports fit the switch.
- Power at PD accounts for the standards boundary after allowed channel loss.
Negotiation is not one number
IEEE 802.3bt extends power classification and can use mechanisms such as multi-event classification, LLDP, and Autoclass. A PSE and PD may interoperate at a lower available level when the source cannot provide the PD’s preferred class. Exact port configuration and device behavior remain product evidence.
Passive PoE boundary
“Passive PoE” is not an additional IEEE Class. Proprietary sources may apply fixed voltage without the standards-based detection sequence. Cable Check Lab therefore never converts a passive voltage label into an IEEE compatibility verdict and treats unknown pairset or polarity as a stop condition.
Primary and industry sources
- IEEE SA — IEEE 802.3bt-2018Four-pair PoE amendment scope and extended classification.
- Ethernet Alliance — Overview of IEEE 802.3btTypes, Classes, PSE power, and power available at the PD.
- Ethernet Alliance — Gen2 PoE Certification technical briefType 3/4 power, classification features, and standards-based interoperability.
- Ethernet Alliance — PoE Certification ProgramDistinguishing IEEE-based products from proprietary powering implementations.
- Cisco — PoE detection, classification, and switch budgetOperational port allocation, LLDP, and total-budget behavior.
Interpretation policy
These tools calculate entered values or compare public declarations. They do not certify a channel, identify an exact product, approve an installation, or measure negotiated power. Use a suitable PoE tester, cable certification equipment, switch telemetry, and exact product documentation where the result calls for them.
Last reviewed: September 2, 2026.