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How can I see what the power consumption and/or distribution of my pi is via terminal?

I can only connect to the pi in question via ssh. So I can't see the "lightning bolt".

I am concerned about something plugged into the pi's 5V pin, and would like to see if there is a way to view how the pi is distributing power (if that's even a thing that CAN be viewed) to its various pins, and how much power the pi is consuming as a whole, stuff like that.

Like how vcgencmd measure_temp and top are very useful for their respective functions. Is there an equivalent for power consumption and/or distribution?

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    The lightning bolt should be accompanied by Under-voltage detected! in the system log. – goldilocks Dec 20 '19 at 16:04
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vcgencmd get_throttled will show current/past under-voltage - which is what the lightning bolt / Red LED show.

The Pi has no means to monitor current.

Latest bits are

0: under-voltage
1: arm frequency capped
2: currently throttled
3: Soft Temp limit reached  3
16: under-voltage has occurred
17: arm frequency capped has occurred
18: throttling has occurred
19: Soft Temp limit has occurred
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According to the comment below, the following is obsolete.

A little Google-fu finds this: https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=82373&start=75#p739517 which may be the answer.

NB: The following is copied from the link above to comply with the Stack Exchange policy of not posting only links. This is not my work.

    import RPi.GPIO as GPIO , time

    redLED=35
    GPIO.setmode(GPIO.BCM)
    GPIO.setup(redLED, GPIO.IN)

    powerlow=0
    while True:
            if(GPIO.input(redLED)==0):
                    print "POWER dipped below 4.63v"
                    powerlow += 1
            else:
                    powerlow =0
            if (powerlow  > 3):
                     print "Low power for " + str(powerlow) + " seconds"
            time.sleep(1)

Something simpler could be vcgencmd measure_volts <id> Shows voltage. id can be one of core, sdram_c, sdram_i, sdram_p, and defaults to core if not specified.

That came from this link: https://elinux.org/RPI_vcgencmd_usage. However, I doubt that will really do what you want. You could try both and stick with the one that actually works. On a properly-operating Pi 3B+ the core voltage indicated by that command is 1.20 V.

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    That code will only work on very old Pi. The power LED is NOT on pin 35 in current models. – Milliways Dec 20 '19 at 23:29
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    Thanks. I didn't know that. – Bob Brown Dec 20 '19 at 23:57

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