ABB Busch-Universal 6593U-500 Manual De Instrucciones página 88

Fig.3
1.1.1.52
Busch Universal Master Dimmer 6593U-500 with
pushbutton mode
The "N" terminal is only necessary in special cases (e.g.
noise emission of the load when the dimmer is switched
off). It has no influence on humming noises from a
transformer which is connected and switched on.