This article covers the wiring of the HF-75S Exhaust fan for the Aurora Fiber Machines.
For more information on the fan: HF-75S 3 Inch 27 CFM MIXED FLOW INLINE FAN
Main Label
Factory wiring is for the High Speed, 29W, 120V, .50A and 27CFM
Internal Wiring to the Fan
Typically a Blue wire is used for the Neutral and a Brown is used for the Line. If a Different wire color is used on your plug, double check the wire colors in the junction box on the Fan itself.
Schematic on the back of the cover: Cable is wired on the right, fan wiring is on the left.
High speed wiring is shown below. To change to low speed, move the Brown (Grey), Line wire to the right terminal, LB with the Red wire (Supposed to be brown per the fan junction box cover)
Plug Connections to Test if Modifying the Fan Wiring
- Blue Neutral goes to the Left Pin with the orientation shown
- Center Pin is no connection
- Brown/Grey wire goes to the right Pin with the orientation shown

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