Check your RJ-45 outlet for power using the PoE AF/AT/BT tester. The PoE tester connected to an RJ-45 outlet, tests the cabling infrastructure for the presence of power—either IEEE 802.3af, IEEE 802.3at or IEEE 802.3bt standard or legacy detection. The PoE tester also identifies the existence and type of the Power Sourcing Equipment (either switch or midspan) in your network.