You need to connect the Light to a Clock. Clock: Build a Timer and two Logic Blocks. Connect the Timer to Logic Block 1. Connect Logic Block 1 to Logic Block 2. Connect Logic Block 2 to the Timer. Then configurate Logic Block 2 into a NAND-Gate. Now you can connect the Lamp to on of the Logic Blocks and change the speed by changing the Timers Ticks.

I made a flashing light system so you can actually make them flash

But it does not work without this, also the moving in circles needs a bearing to turn the light around