Powering a Pi 4 the right way
-
I have a 1.01 version Duet 3 Mainboard that I am trying to run with a Pi4 attached via the included ribbon cable. I am getting low voltage warnings regardless of whether I use the internal power supply or if I add an external voltage regulator. From what I can find, the Pi4 had too great of power requirements for it to be powered from the board, especially if DotStar/NeoPixels are used. I have not tried to add LEDs yet, but I plan to. What is the proper way to make sure that the Pi and the LED's are powered correctly and the grounds are maintained for all of the components?
My current setup:
24v 15a Power Supply connected to Power In, Out0 Power In, and Power in on a 5v 10a power regulator.
5v out on the power regulator is also attached to EXT 5v
Internal 5v Jumper is removed.I assume this is not going to work as I am still getting power drops on the Pi. Should I create my own SBC Cable that exposes the power and ground pins and power via the GPIO so the common ground is maintained? Can the Pi be powered via USBC when the Shipped SBC cable is used? What is the "right" way to do this?
-
The best way would be to power the Pi with it's own separate 5v PSU such as the one that may have come with it if bought as a kit. https://www.raspberrypi.com/products/type-c-power-supply/
-
@kiendeleo Best way is to just use the Pi supply that come from a reputable Pi4 kit. Second best is to get a USBC connector for the Pi and connect only up the voltage lines and run that to a dedicated 5v supply. I use a 5V 18A supply and power the PI and then a second line to the Duet3 via 5V_ext_in this way. No issues and should have enough head room to run the Pi + its screen, the 5v parts of the Duet board and a modest number of LED's safely.
Just using the kit PSU has the advantage of just leaving the Pi running 24/7 Which increases the life expectancy of the SD card quite a bit IMO -
@phaedrux said in Powering a Pi 4 the right way:
The best way would be to power the Pi with it's own separate 5v PSU such as the one that may have come with it if bought as a kit. https://www.raspberrypi.com/products/type-c-power-supply/
What would be the proper jumper settings for 5v power on the duet3 when the pi is powered in the fashion you describe?
-
@kiendeleo said in Powering a Pi 4 the right way:
I am getting low voltage warnings regardless of whether I use the internal power supply or if I add an external voltage regulator. From what I can find, the Pi4 had too great of power requirements for it to be powered from the board, especially if DotStar/NeoPixels are used.
I have a Pi 4 on mine, it's never given the slightest trouble with the Duet running from 24V.
You could have a faulty IDC cable?
Note that if you are using any kind of extension header on the Pi connector to clear a heatsink etc., many of the ones sold have out-of-spec pins (thin rectangular ones instead of around 0.6mm square) and do not give reliable connections.
I have the Pi cable looped under the Duet board, it just! reaches.
(The stray blue wires in the middle are a temporary cable for an accelerometer).
-
@rjenkinsgb The Pi4 is know to draw too much current to power from the Duet Board. Maybe the 6HC handles it a bit better but the mini5 your just asking for trouble.
-
@nuramori said in Powering a Pi 4 the right way:
@phaedrux said in Powering a Pi 4 the right way:
The best way would be to power the Pi with it's own separate 5v PSU such as the one that may have come with it if bought as a kit. https://www.raspberrypi.com/products/type-c-power-supply/
What would be the proper jumper settings for 5v power on the duet3 when the pi is powered in the fashion you describe?
Which Duet3?
If it's a MB6HC, with the Pi externally powered, and the MB6HC externally powered by 5V applied to 'EXT 5V' (which I think is one of the options discuissed in the thread) then I believe all three power jumpers should be off (i.e. open, no jumper fitted). That's what I do and it works for me.
However, I note that https://duet3d.dozuki.com/Wiki/Duet_3_Mainboard_6HC_Hardware_Overview#Section_5V shows three jumper options, with the warning "no other jumper configuration is recommended or supported", so this is an unsupported configuration - I do it because I keep the MB6HC logic running even when the motor drive supply (24V) is off.
-
By way of wrapping up this thread, the solution I found that works well is as follows:
Power Supply 24v to the board, a 5v Converter, and a USBC Converter. The 5v converter is wired to the 5v external power header on the board with the jumper selected to the External 5v. The 5v converter is also wired directly to the Neopixels that I am running to ensure that they get sufficient power in case there is a limit through the board ( I am using 60 Neopixels for this printer) only ground and signal are hooked to the LED header on the board. I am powering the Pi4 off of the 24v to USBC converter.
Links to the parts on amazon:
24v to 5v converter: https://smile.amazon.com/gp/product/B01M03288J/
24v to USBC Converter: https://smile.amazon.com/gp/product/B07ZQB6S3L/ -
undefined kiendeleo has marked this topic as solved
