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optiPoint 410/420 FAQ (general)

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Power over LAN

My optiPoint 410/420 phone only supports power class 0 (default). How to setup the corresponding PoE compliant switch to reserve lower power?

Some earlier hardware models of the optiPoint 410/420 phones did not support power negotiation feature according to the IEEE 802.3af standard. For details refer to the tables available on the optiPoint power supply and PoE classes page (Refer to Device Version columns).
To avoid that the LAN switch reserves more power than necessary and thus can't be able to feed PoE to all powered devices connected on its ports, each LAN port should be configured with a specified Power Class.
This is normally part of each Ethernet LAN Switch configuration / administration and should be specifically evaluated product by product.
See also:

Can I run an optiPoint 410/420 with both local and PoE Power Supply at the same time?

Although the phone will neiter break nor stop functioning, this practice is not recommended and so to avoid.
With both the Local Power Supply and the PoE supply the Power Class negotiation will not run properly, this happen because the IEEE802.3af standard requires a power-less state for correctly perform the class negotiation (So no Local Power Supply should be active during the negotiation phase).
Thus in this case the Power Class will be set to 0 (default): If the power negotiation is done first and the Local Power Supply is then connected, the initial negotiated Power Class will not be changed.