Common GND on Duet2 Wifi?
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Is all the gnd/- terminals common on Duet2.
Thinking of Heaters, Fans etc.
Want to reduce the amount of cabels running to the printer head/extruder assembly. -
@TomasL No they are not in general any switched "highish" power output (like a heater or fan) will be switching on the low/ground side of things.
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@gloomyandy Ok, so I cannot run a common to fans, heaters and the z-probe
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@TomasL
Depending on what is needed, the positive voltages can be used together.
But then also pay attention to the cable cross-section -
I cannot understand why low-side switching is used (Apart from being cheap and easy).
I know it is easier, But High side is safer and, one get a common ground. -
@TomasL It's because the switching is done by N-channel MOSFETs, and these need to be placed after the load, and switch to ground. I don't know enough about electronics to know exactly why these are used, but there's a comparison of N Channel vs P Channel MOSFETs here: https://www.icrfq.net/n-channel-vs-p-channel-mosfet/
I think mainly that N-channel MOSFETs are better for fast switching, so are more suitable for PWM applications such as the heaters and fans.
Instead of a common ground, you can have a common +V? You couldn't have both, whichever way the output was switched.
Ian
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I think mainly that N-channel MOSFETs are better for fast switching, so are more suitable for PWM applications such as the heaters and fans.
I use P-channel MOSFETs a lot, but the fact remains that they dissipate much more heat - up to a magnitude more than the N-types -, so cooling becomes a major problem.
Instead of a common ground, you can have a common +V
Yeah, that's what, on the continent, British cars were famous of - or feared …
