When you have a new lamp and need to connect it to the ceiling outlet, you need a ceiling plug. In Swedish homes and offices built or renovated after 2020, the rectangular DCL plug is used. In older buildings a round plug with two or three pins is used.
These are the common types of ceiling outlets:
DCL is the long rectangular connector with three flat pins.
A round connector with one flat side and a pin sticking out is earthed.
A round connector with one flat side and two holes is unearthed.
A round connector with one flat side and three holes is unearthed.
A fully round connector with two holes is an unearthed ceiling outlet.
Here you will find all the common types of ceiling plugs.