When you buy all Cisco IP phones, without the power adaptor, so how to work?
There are 3 options for connections.
1) Buy power transformer (CP-PWR-CUBE-3) directly; suitable for few Qty, will be an economic method.
2) If you have POE switches, will be better. Connect by a RJ-45 cable directly.
3) For long-distance consideration within 100 meters, you also can connect with Power Injector (CP-PWR-INJ).
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