Duet Wiring
Contents
PWM MOSFET control
All power element which are controlled are connected to PWM controlled MOSFETs which drain current to the ground ('sinking' connections). These sinking lines are indicated by an arrow. PWM frequency varies depending the application and is user adjustable for controlled fans. MosFET may fail and stay permanently conductive, in this case the connected element will go full power with the only possibility to stop being to shutdown the power supply, which is only possible if the Power Supply could be stopped via the PS-on signal. See Safety page.
End stops connection
Signal shall never exceed 3.3V. Safety shall be provided in case of ground wiring fault.
The signal line is connected to an on board LED (see schematic), so if endstops are electronic circuits, they shall be able to drain sufficient current through the LED to rise signal to high. This shall be taken into account if using a voltage divider (to limit the signal voltage).
Duet 0.8.5
Main wiring
All positive fan pins are connected to Vin.
The pinouts are on the back of the board (V 0.8.5), a KiCAD export shows the back below for reference (this is the view from the bottom of the board, so is mirrored):
There is more detail on the pinouts on the Duet pinout page.
BED and chamber heater SSR wiring
Chamber heater use E1 output and thermistor input.
5V controlled fan
Duet 0.6
Beware of the Bed, heater and fan connector polarity, which is different from the 0.8.5 board
Main wiring
The back silkscreen on the Duet 0.6 contains further information on the pinouts, it is reproduced below
5V controlled fan
