Current consumption raspberry pi

Current consumption raspberry pi

I am working on raspberry pi for my project and my concern is towards energy consumption part of the pi. When we turn on the pi in steady state the current consumption is around 380mA. I have only lan connected to pi and all the other peripherals are unused. I would like to know the reason of this baseline current consumption. What are the constituents which sum upto the usage of 380mA of current? Because when i run my application the maximum current is around 460mA and there is no huge margin from the baseline to optimize further from my application.
It would be of great help if you can help me in understanding the baseline current consumption and if there are anyways by which I can reduce this current (for eg: operating in low power modes).

Many thanks in advance,

Re: Regarding current consumption of raspberry pi

Re: Regarding current consumption of raspberry pi

About a third of that is the USB/NIC chip. A fair bit of power is lost in the LDO (though that won’t show in your current readings). I don’t know, but I guess a large chunk is due to various parts of the SoC being enabled when they don’t have to be. I don’t know about the rest.

Does your application require the use of USB and ethernet? If not, there’s a way to disable them for significantly reduced power usage.

Re: Regarding current consumption of raspberry pi

I do not have the model A version of the board with me but I would like to know how GPU can be switched off and also about lowering the clock speed. Presently I am clocking at the default rate itself.
Much appreciated for your response.

My application does not need either USB or ethernet. I am using LAN just to ssh from host and send the necessary commands/ scripts to run. I did not interface HDMI and keyboard so that I did not want to burn more current on these peripherals and instead used only LAN. Please help me in disabling the peripherals. Even I am looking for them.
Many thanks in advance.

Re: Regarding current consumption of raspberry pi

Re: Regarding current consumption of raspberry pi

You can’t entirely disable the GPIO as the Pi will not run without it. The Pi is a GPU with a tiny ARM core tacked onto it. The hardware including memory control, GPIOs and SD card interface all run through the GPU.

You can disable to video output, which should same a milliamp or two. Try tvservice -o.

Note that the GPU is designed to be used in low consumption devices and will automatically turn off any parts of itself that are not required at the time.

As others have said, best option for low power (if you don’t need LAN/keyboard/mouse) is to get a model A. The USB/LAN chip is quite power-hungry, so the saving by not having it is about 30%. You still have the option of plugging in a USB-LAN adapter if needed.

Other things you can do is to remove the 3.3V regulator and supply 3.3V directly to the circuit (via the GPIO pins). There are some issues with not having 5V on the board, but there are posts about that somewhere. Search for something like «running Pi on 3.3 volts».

Re: Regarding current consumption of raspberry pi

Where did the idea of disabling GPIO come from? If it was anything I said, I would like to clarify that I was only talking about disabling USB and potentially, once there is an open blob, parts of the SoC.

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Current consumption raspberry pi

Hello all, I’m new to the forum

I ran some checks on the current consumption of various Raspberry Pi models as a precursor to a battery-powered project. I thought I would post the results here in case they are useful to someone else.

Raspberry Pi Models

  • Raspberry Pi 1 Model B
  • Raspberry Pi 2 Model B
  • Raspberry Pi 3 Model B

Multimeter

  • I used a MUKER-TM103:
  • I ran each test for 30 minutes then doubled the displayed mAh figure e.g. 75mAh after 30 minutes = 150 mA
  • The only exception was the raspivid test because the 8GB card wasn’t big enough to store 30 minutes with the full Jessie distro. Therefore the raspivid tests were ran for 20 minutes then tripled.
  • I have no idea how accurate the MUKER-TM103 is. The precision seemed good enough for my needs.

Distros

  • Raspbian Jessie (2016-03-18)
  • Raspbian Jessie Lite (2016-03-18)
  • Diet Pi (v116)

Stock Idle

  • Fresh image on Toshiba Exceria 8GB card
  • Updates done

Disable HDMI

    Re: Current Consumption Figures

    I question your results; especially the PI 3B. Did you think of loading the PI (all four cores doing something. )? The 3B easily exceeds 2000ma in normal usage, and often goes as high as 2500ma. In my robot I’m using a 3amp DC-DC 12v -> 5v converter and an 80amphr gel cell. (its an R2D2 look-alike, fairly heavy, and frankly most of its mass is going to be the 12v gel cell).

    Anyway, based on your chart above, I think you are going to be way under-estimating your power consumption.

    Re: Current Consumption Figures

    I question your results; especially the PI 3B. Did you think of loading the PI (all four cores doing something. )? The 3B easily exceeds 2000ma in normal usage, and often goes as high as 2500ma. In my robot I’m using a 3amp DC-DC 12v -> 5v converter and an 80amphr gel cell. (its an R2D2 look-alike, fairly heavy, and frankly most of its mass is going to be the 12v gel cell).

    Anyway, based on your chart above, I think you are going to be way under-estimating your power consumption.

    I was going to agree with you initially but went back and re-read the post. I think the figures are accurate as a baseline for a pi camera recording a static view — and that’s all. For a off-the-grid camera recording project it makes sense.

    I’m wondering if underclocking / undervolting would have any effect on the power draw.

    Re: Current Consumption Figures

    I question your results; especially the PI 3B. Did you think of loading the PI (all four cores doing something. )? The 3B easily exceeds 2000ma in normal usage, and often goes as high as 2500ma. In my robot I’m using a 3amp DC-DC 12v -> 5v converter and an 80amphr gel cell. (its an R2D2 look-alike, fairly heavy, and frankly most of its mass is going to be the 12v gel cell).

    Anyway, based on your chart above, I think you are going to be way under-estimating your power consumption.

    Thanks for your reply. I have no way of ascertaining how accurate the MUKER-TM103 is, but really what I was after was a comparison between the models so I know which to work with (in my case, Raspberry Pi 2B). I did note that my figures seem to tally up with others I have seen elsewhere e.g. the saving by disabling HDMI and USB bus.

    Accuracy unknown, precision good

    I didn’t load the cores because I have no need for that in my project. Each test takes about 5 hours to complete so I had to limit the scope.

    Re: Current Consumption Figures

    Got to ask what is your definition of «normal usage».

    Mine doesn’t go anywhere near 2A@5V in normal use.

    Re: Current Consumption Figures

    tweak42 wrote: I was going to agree with you initially but went back and re-read the post. I think the figures are accurate as a baseline for a pi camera recording a static view — and that’s all. For a off-the-grid camera recording project it makes sense.

    I’m wondering if underclocking / undervolting would have any effect on the power draw.

    Re: Current Consumption Figures

    Got to ask what is your definition of «normal usage».

    Mine doesn’t go anywhere near 2A@5V in normal use.

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    Unfortuneately those usb ammeters are often wildly inaccurate — especially at less than 100mA

    E.g. your figure of 28mA for «powered down» is quite far off — 80mA is more realistic for all pi.

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    mikerr wrote: Unfortuneately those usb ammeters are often wildly inaccurate — especially at less than 100mA

    E.g. your figure of 28mA for «powered down» is quite far off — 80mA is more realistic for all pi.

    Thanks for your reply. I suspect that the accuracy may not be a strong point. What I find interesting is the precision. Repeat the tests and I get the same figures, time after time, consistent across each model and varying significantly between models.

    I’d love to have a bench power supply but I can’t warrant the expense.

    The main purpose of what I did was for comparison purposes between models, rather than getting accurate figures. I’m doing some rundown tests on battery packs now which should give me some more data.

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    First, I don’t believe you’ve even measured it! (place a good ammeter in series with the 5v power feed so that you can actually measure the current while using your PI)

    Second, normal use is completely subjective, isn’t it? If I tell you what normal use is, you’ll disagree and tell me that I’m wrong. who cares. I actually use my PIs. all of them are functioning as one server or another, all of them are remote desktop PCs, two of them are also GPIO controllers, all of them have usb connections, two of them also have ethernet connections, and most of them are using at least two cores all of the time. they get used! They are real computers (not toys) and they actually process data all the time. for me that’s normal use.

    I used to use multiple desktop towers to do this same work (mostly e-machines). I have completely replaced my compliment of towers with Raspberry PIs. My entire functioning network of personal computers (besides my mac, and my HP notebook) are Raspberry PIs. and they are the network workhorses. Again, they are being used.

    I have actually measured the PI current on the 5v supply during operations (PI 3B) and they routinely exceed 2000ma/ and they get hot (all of them have heatsinks) but without throttling. My 2.0A PSU was not enough to keep the 3B running right. They are on dedicated 2.5 or 3.0 amp PSUs now.

    You may claim what you wish. I am finding it hard to believe that my situation is any different than anybody else’s setup, with the exception of Rive; no, I don’t not deliberately overdrive my PI just to experiment with running it at the high end (not even). I just use them, in a normal way (as personal computers).

    Re: Current Consumption Figures

    Hi. i am new to this forum and i have to ask did you think of loading the PI? The 3B easily exceeds 2000ma in normal usage, and often goes as high as 2500ma. In my robot I’m using a 3amp DC-DC 12v -> 5v converter and an 80amphr gel cell. Anyway, based on your chart above, I think you are going to be way under-estimating your power consumption.

    Re: Current Consumption Figures

    Re: Current Consumption Figures

    Interesting to contrast the reported power consumption figures in this thread with those of the Foundation here.

    Must make some measurements myself.

    Re: Current Consumption Figures

    To throw another cat amongst the pigeons — real world figures.

    RAVPower Element 10,400 mAh power bank:

    Pi 1B displaying raspivid output via HDMI plus the edimax wifi running.

    At the start, the output was shown as 5.05 V with a fairly stable 0.60 A.
    The voltage and mAh figures were noted at various intervals.
    At 11 hours the voltage was down to 5.00 V.
    At 11:14 the Raspberry Pi powered down, showing 6,787 mAh.

    Please feel free to correct my calculations:

    10,400mAh @ 3.7V = 7,696mAh @ 5V
    The Pi powered down at 6,787mAh, which is around 12% less.
    No published figures on conversion losses for this product that I could find.

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    How Much Power Does Raspberry Pi 3B+ Use? Power Measurements

    Since the original Pi came out I’ve been interested in how much power it consumes. It’s become something of a launch week tradition to publish a new chart and some data. So much so that several people ask for it on launch day. This time the first was within 7 minutes of launch, which is a new record…

    Did you test the energy consumption?

    The main reason I do this is that, if you are running a Pi on batteries, you need to be able to know how long it will run for. So I don’t go in for complicated benchmarking tests (although arguably perhaps I should, now that the CPUs are getting more powerful and hungrier) but a straightforward batch of tests that I’ve always used. It gives you an idea and enables you to work out your power budget.

    With just an HDMI screen and a USB keyboard/mouse dongle connected, the Pi is powered using my bench power supply at 5.2V (supply current limit = 3 Amps) wired, via the eMeter’s calibrated 20 Amp shunt, to the uUSB power input on the Pi.

    eMeter, clamp meter and bench PSU all being used to check power consumption of Raspberry Pi 3B plus

    Current and voltage are measured using my eMeter (also used my clamp meter to confirm this time) and calibrated shunt whilst performing four different activities. “Shooting video” is done without saving the video output to the SD card. Watching video is done with a 1080p video on the SD card. The rest is self-explanatory. The camera module is unplugged for all but the shooting video test. The Pi3B+ was connected to wifi, but no bluetooth devices were in use.

    Understanding the Limitations

    It’s important to understand the limitations of any equipment, tests and results. Comparing the readouts on the bench power supply, clamp meter and taking the actual data readings from the eMeter gives a reasonable degree of confidence in the results (when they agree, which they did).

    The eMeter gives time-averaged readings (updated several times per second) to two decimal places of an Amp, which is good enough for our purposes. It won’t give a true picture of peak instantaneous current e.g. on power-up of the ARM cores from idle. This matters only when selecting a PSU to run your Pi, and you already have the official recommendations of a 2.5 Amp PSU for that. What we’re interested in is power usage over time, so you can work out what size battery pack or solar panel you will need.

    I’ve never done power tests while using ethernet. But the new Gigabit ethernet chip definitely chews through more power than the previous Pi models (even when not in use). At some point I will consider adding this data to the chart/table, but not today. It would require measurement of “all of the Pis” which I haven’t got time to do right now – and you want your data NOW!

    Results

    Raspberry Pi power usage table incorporating Pi 3B plus

    Raspberry Pi power usage chart incorporating Pi 3B plus

    Commentary

    The thing that jumps out at you if you compare 3B+ with 3B is that it uses at least 170 mA more current – even at idle. This is due to the new Gigabit ethernet chip. I believe there will be a facility to switch this off if not used (at some point).

    This seems to account for most of the differences except for while under CPU load. Whilst watching or shooting video, the GPU is handling most of the work, and this is unchanged on the new chip. So it’s not really surprising to see only small differences if you strip out the effect of the new LAN7515 chip.

    Where we DO see a significant difference is in the loading of LXDE while under CPU load. You can see that this is significantly higher than with the Pi3B. It’s probably loading faster, but you don’t get ‘owt for n’owt. Faster processing takes more power, and that’s what we can see in the chart.

    Raspberry Pi 3B+ uses at least 170 mA more than its older sibling the Pi3B, but can use significantly more when the ARM CPUs are being driven hard.

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