Hello!
I couldn't find much documentation on the `usb_max_current_enable` option (also found in raspi-config Performance settings) and wanted to confirm it is safe/reliable to use.
For context, we are powering a Raspberry Pi 5 off of the GPIO pins and as a result, are using 3A and as documented, this means that each USB port is current limited to 600 mA (since using a 3A). However, when plugging in a USB web cam, a keyboard, and a USB to Serial Adapter for controlling servos, the current limit is preventing both from running reliably at once. When disabling the current limit (setting usb_max_current_enable=1), all those peripheral devices are now working more reliably. We confirmed this behavior using a usb current reader (like this[https://www.digikey.com/en/products/det ... 3EALw_wcBl]).
Thus, the core of my question is: What risks are associated with overriding this setting when powering with 3A? What important things should I be aware of when doing this? In this situation, is it reasonable to enable this setting?
Any insight of potential risks or additional things to look out for when making this change would be greatly appreciated! Thank you!
Here is the documentation I have been looking at thus far:
https://www.raspberrypi.com/documentati ... hosenpower
https://www.raspberrypi.com/documentati ... al-bus-usb
I couldn't find much documentation on the `usb_max_current_enable` option (also found in raspi-config Performance settings) and wanted to confirm it is safe/reliable to use.
For context, we are powering a Raspberry Pi 5 off of the GPIO pins and as a result, are using 3A and as documented, this means that each USB port is current limited to 600 mA (since using a 3A). However, when plugging in a USB web cam, a keyboard, and a USB to Serial Adapter for controlling servos, the current limit is preventing both from running reliably at once. When disabling the current limit (setting usb_max_current_enable=1), all those peripheral devices are now working more reliably. We confirmed this behavior using a usb current reader (like this[https://www.digikey.com/en/products/det ... 3EALw_wcBl]).
Thus, the core of my question is: What risks are associated with overriding this setting when powering with 3A? What important things should I be aware of when doing this? In this situation, is it reasonable to enable this setting?
Any insight of potential risks or additional things to look out for when making this change would be greatly appreciated! Thank you!
Here is the documentation I have been looking at thus far:
https://www.raspberrypi.com/documentati ... hosenpower
https://www.raspberrypi.com/documentati ... al-bus-usb
Statistics: Posted by julia! — Mon Sep 15, 2025 8:38 pm