A light-emitting diode (LED) luminaire comprises an emergency-operated portion comprising a rechargeable battery with a terminal voltage, a self-diagnostic circuit, and a node modulator-demodulator (MODEM). The LED luminaire can auto-switch from a normal power to an emergency power according to availability of the normal power and whether a rechargeable battery test is initiated. The self-diagnostic circuit comprises a clock and is configured to initiate self-diagnostic tests and to auto-evaluate battery performance according to test schedules with the terminal voltage examined and test results stored. The LED luminaire further comprises a remote controller configured to initiate control signals with phase-shift keying (PSK) signals transmitted and to collect test data to and from the node MODEM. The node MODEM is configured to demodulate the PSK signals and to send commands to the self-diagnostic circuit to request responses accordingly.