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    PoE Power Budget Calculator (Watts)

    How much power does a PoE switch need per port?

    The PSE port must source the device draw plus the resistive cable loss, so per-port PSE power equals PD watts plus I²R loss in the channel. IEEE 802.3af allows up to 15.4 W per port, 802.3at up to 30 W, and 802.3bt Type 3 and Type 4 up to 60 W and 90 W. The tool also confirms the device draw stays within each standard's PD class maximum.

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    Use the PoE Power Budget Calculator (Watts) to get an exact answer for your inputs.

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    Related questions

    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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