* **Output inverted** - Most setups will use `No` for this setting, but if you have a fan circuit that flips the output, the polarity can be reversed with this setting
* **Fan switching temperature** - The temperature above which the fan will be turned on.
* **Fan hysteresis** - The number of degrees below the fan set point that fan will be turned off. This is used to avoid oscillation around the set point resulting in the fan turning on and off rapidly.
* **PWM Fan frequency** - Sets the PWM fan output frequency. See the fan controller specifications for the correct frequency.
> Note! Speeduino fan output is control signal only. Not capable of driving fan motor directly. So relay is required to turn fan on and off or separate fan controller in case of PWM fan.{.is-info}
PWM Fan Curve sets the fan duty based on engine coolant temp. Duty range is 0-100%, but note that depending on the fan controller, the duty range can be different. In example 10-90% or the fan controller will go to fault state. See the fan controller specifications for the valid range.