Lässt sich ein Dimmer am Stromausgang vom Netzteil anschließen wenn dieses keinen hat?

The LED power supply's purpose is to keep the voltage and current at a constant rate, and thus it controls dimming from inside the power supply. If the power supply does not have a separate pair of wires to connect a dimmer, then your last hope is to check for built-in dimming adjustment. This is usually in the form of screw hidden underneath a round rubber plug on the power supply's that have a metal case (water resistant).

I thought those lights came with a dimmable Meanwell power supply. What power supply do you have? Depending on the model of power supply you may need an external dimmer control. They are inexpensive. Or some power supplies have adjustments you make through holes in the case with a small screwdriver.

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