Updated Beginner's Guide (English) (markdown)

Beginner's-Guide-(English).md

@@ -223,9 +223,13 @@ The default setting is now complete and theoretically it is now possible to prin
 
 This custom firmware offers some innovations in the printing behavior and also pushes the physical limits of the printer to the full without damaging it.
 
-Two settings are very important for this:
+These settings are very important for this:
 
-### Size of the print bed (Mega S and Mega Pro)
+### Size of the print bed (ONLY Mega S and Mega Pro)
+
+The Mega S and the Mega P have a larger print bed (240x220 mm) on which the glass plate is attached with side brackets. The print head or the nozzle cannot cover the entire bed and reach every corner, but it is possible to print larger than 210x210mm, as the hardware allows it. That is why the firmware allows a larger print space to be used with these two printers than is specified by the manufacturer.
+
+The following values must therefore be entered in order to use this and to place the component back in the middle of the bed:
 
 `X (Width) = 225 mm`
 
@@ -241,6 +245,20 @@ In order to achieve the best print result, which is possible with a 16 MHz Atmel
 
 [[https://raw.githubusercontent.com/knutwurst/Marlin-2-0-x-Anycubic-i3-MEGA-S/master/images/max_resolution_cura.jpg | width = 600px]]
 
+### Maximum fan speed
+
+The component fan, which blows directly under the nozzle to cool the filament, is controlled in speed via pulse width modulation (PWM). There is a simple procedure behind the complicated term: The power supply (12V) is switched on at regular intervals (PWM frequency) for a certain period of time (PWM duty cycle). After this period of time, the power is switched off again. The longer the ON phase, the faster the fan rotates.
+
+In the original firmware, Anycubic limited this maximum PWM duty cycle to the value **0.7** or multiplied any set value by 0.7. Thus, a fan set to 100% only rotated at 70% of its possible power.
+
+There is no such lock in this firmware, so it is easily possible to install other (quieter) fans that can be operated continuously with a full 12 volts.
+
+However, this has the consequence that the original fan from Anycubic now rotates 30% faster than it should and thus the component may cool down much too much. Since the air flow is also not ideal, it can happen that the nozzle is cooled down too much, and thus temperature errors occur in the print.
+
+**For this reason, the fan in the slicer must not be set above 70%!**
+
+[[ https://raw.githubusercontent.com/knutwurst/Marlin-2-0-x-Anycubic-i3-MEGA-S/master/images/max_resolution_cura.jpg | width = 600px ]]
+
 
 ## 8. Start and end code