Hi,
I am using a PiPower v2 on my Raspberry Pi 4B and experience frequently “kernel: hwmon hwmon1: Undervoltage detected!”.
I’ve tried several power supplies, have been monitoring the input voltage of the PiPower.
Using the same power supplies directly on the Raspberry without any problems.
Any thoughts on this? Shouldn’t the UPS deliver constant output voltage (even in case of low input voltage)?
Regards,
Stefan
Suggest providing a video of the problem for us to see.
What is the voltage of the battery measured when the low voltage prompt appears.
Did you fully charge the battery,? Does the Raspberry Pi also show the low voltage prompt when fully charged.
Hi, I am having the same issue.
When on official raspberry power supply the pi4b has no issue.
When using the pipower v2 there are constant power warnings.
When on AC and a dummy load of 1A I get a voltage of 4,7 to 4,8V with a ripple of arround 300-400mV.
When unplugging the AC adapter the voltage rises to 5V with a ripple of 30-40mV and stopping the power warnings.
Tried different AC adapters. All show the same effect.
Gr
Have you fully charged the battery and then connected the PiPower to the PI4 to start it? Are you seeing any low voltage warnings?
When the battery voltage is too low, a low voltage warning will indeed appear.
If you are playing while charging, with the PiPower connected to a power source, it’s recommended to use the official 5V 3A power supply from Raspberry Pi.
Using a third-party power supply may also result in low voltage warnings.
Yes official power supply works fine. No warnings. I get 5,18V on it. When I put the pipower in between it only outputs 4,7-4,8V when fully charged. When I unplug it from AC the voltage goes to 5V.
The warnings on home assistant are when using the pipower. Afterwards is on the official supply.
We recommend using the official Raspberry Pi power supply for charging.
Could you please provide a video of the issue? It will help us analyze the problem better.
I am on official supply. What are you looking for in video?
Gr
I am running into the exact issue with my RPi4 running the PiPower v2. Voltage is >
5v when running off of the battery, but drops below 5v once I plug in. Tried multiple charges able to handle 3A or greater.
Nice to know I’m not the only one with this issue.
Looking forward to getting this resolved.
The current version of the PIPower V2 is designed this way.
The official 5V 3A power supply needs to simultaneously power the Raspberry Pi 4 and charge the battery. The total demand may require a high current, which can lead to the power supply being overloaded and the output voltage being pulled down.
Additionally, when the external power source is connected, the UPS switches from battery boost mode to passthrough mode. This process goes through many interfaces and connections, which can also cause a voltage drop.
Even if the output voltage decreases, under normal circumstances, there should not be any issues with the Raspberry Pi shutting down or rebooting.
We recommend using the official 5V 3A power supply for charging. Please check if the output voltage remains around 5V while charging and using the device simultaneously.
We also suggest using a multimeter to measure the output voltage.
Even if the output voltage is slightly above 5V, it shouldn’t affect the Raspberry Pi’s power supply or cause it to shut down or restart.
