A power supply module for a lighting system is directly mountable onto a special cover plate for a standard electrical junction box. The power supply module is provided with a plug assembly that mates with a socket assembly incorporated within the special cover plate. The power supply circuit provides an electronically power limited output through multi-conductor connectors. The power supply output is used to connect to luminaires using a multi-conductor cable having multi-conductor connectors that mate with the multi-conductor connectors on the power supply and the luminaires. The luminaires use a circuit to interface between the power supply output and the lamp. The special cover plate is also suitable for receiving a plug assembly incorporated within the base of a lighting base module that can provide temporary incandescent or gas-discharge lighting.