(1) External power supply
As the name suggests, the external power supply is installed in the outside. General voltage is relatively high, the person has a safety hazard, the need for external power. The difference with the built-in power supply is that the power supply is added with a housing, common with streetlights.
(2) Internal power supply
is the power supply installed in the lamp, is generally low voltage, 12v to 24v, there is no safety hazard. This is a common bulb lamp.