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Is it possible to measure (with software, like PowerTOP) the Pi's current power consumption, on my Raspberry Pi?

  • 1
    "On" your Pi... as I think you mean, or "of" your Pi, which others think you mean? – user59377 Jan 4 '17 at 21:03
  • @user59377 - whilst I have up voted your comment, due to its call for clarification... I believe that the OP actually wants to measure the consumption using software running on the Pi - so "on" is correct, and "of" is not. – Greenonline Apr 23 '17 at 11:43
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No. You cannot accurately measure the power consumption of your Raspberry Pi by just software. There needs to be some hardware in place in order to do this and devices rarely have this by default.

The easiest option would be to use a wall outlet power meter or usage monitor. You can buy these for $10-$20 at a local store.

Without such hardware, the best you can get are estimations.

  • i have outlet power meter, but i'm too lazy :D...and for devices with intel cpu i can use powertop. So my idea was to use something like powertop, but for arm ;) – cupakob Oct 8 '12 at 18:23
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    PowerTOP gives you an estimation, not a real measurement. The estimations are intended for comparison when you want to try different power saving features out. For laptops PowerTOP can make better estimations by doing measurements on your battery level and performing calculations. That is something you cannot do on a PC or Raspberry Pi. Read more about it here. – Derecho Oct 8 '12 at 21:05
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    The easiest option would be to use a wall outlet power meter or usage monitor. That's fine if you want to know how much power your setup is using, but not if you want to know how much power your Pi is actually getting. Power adapters and even USB cables can waste significant power. I've read of USB cables dropping a whole Watt or Volt (I can't remember which was said, but they'd be about the same in some conditions). – Nateowami Jan 5 '16 at 11:44
  • I tried using my outlet meter, and it's accuracy was too low. It reported a constant 2 watts, even when the PI was off. – Iain Aug 14 '16 at 0:08
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Your best bet is to use a USB voltmeter/ammeter between your USB power source and the Pi.

USB Voltmeter

In addition, you will require:

  • a USB micro to USB 'A' convertor from the power source to the USB voltmeter;
  • a USB 'A' to USB micro cable from the USB voltmeter to the Pi.

There are many different types ranging from $1 to $5, depending if you want a single display, a dual display, as pictured, or up to a quad display that also shows power (Watts) and charge (Coulombs)

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    This solution is superior to the one proposed in the accepted answer ` wall outlet power meter ` because it factors out the power supply unit efficiency, which is probably not constant over the working range. – Vorac Apr 22 '17 at 20:44
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    @Vorac - please feel free to upvote my answer, if you feel that it is a superior solution. :-) – Greenonline Apr 23 '17 at 11:38
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Whilst you can't directly monitor the power consumption you can obtain information about the operating voltage of the: core (default), sdram_c, sdram_i, and sdram_p (see here for more details).

vcgencmd measure_volts <id>

e.g. To check the core voltage:

pi$ vcgencmd measure_volts
volt=1.2000V
  • Thanks for answer, i wonder why this doesn't work with the new user and works only with pi as user, any idea ? – Vinod Srivastav Jan 2 '18 at 18:35
  • @VinodSrivastav i don't have one here but check pi's groups and add relevant ones to your user (usermod -aG <group> <user>), don't forget to logout and login for the changes to take effect. – Pierre-Alexis Ciavaldini May 22 at 15:39
2

Multimeter in series with a bench top power supply. Or by looking at the bench power supply itself if it has an Amp meter.

Measuring the whole thing (with power supply) won't give you an accurate reading of the Raspberry pi's actual usage since you will also be measuring inefficiencies in the power supply you use.

  • 2
    Measuring with the power supply would however be an accurate representation of the costs associated with the usage. It depends on the goal whether you want to measure before or after the power supply. – Derecho Dec 6 '12 at 8:05

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