Third and last question for today – promised. As mentioned I build up the Avant after purchase piece by piece again. I want to give the engine from painful traffic jam experiences on the A7 – which will employ me the next 12 years around Hamburg, some remedy. Since the cooler has already blessed the time, a new one comes. Instead of the standard single fan engine would like to convert also to the double fan equipped with belt drive. This also has only one engine and drives the second propeller installed in the fan housing passively with. But now it’s tricky: the currently installed standard fan has a 2-pin plug with omitted middle contact. The engine of the future double fan housing has the same plug with mid-clock (= 3-pin). Who knows what the third (mid-pin pole) is needed for. Evidently for an additional fan level on half power? Can I ignore the one? I only have a two-pole control, but I don’t have to connect to the 3 pole fan engine.