dwwaddell
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Re: RasPi power usage measurements ALL Models

Sun Nov 02, 2014 10:16 am

My interest is in using the Pi B+ as an off-the-grid web server. With that aim I don't even need the HDMI connection, only the ethernet and the power is being supplied by a solar-powered battery charger (50000 mAh [claimed] and 1.5W charging from the solar panel). Any idea how much power the Pi uses without HDMI? I need to get it below 750mW (assuming 12 hours of daylight). If I need a GUI, I can come in with VNC (which may also use power).

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davidcoton
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Re: RasPi power usage measurements ALL Models

Sun Nov 02, 2014 11:35 am

1.5W from the solar panel won't be enough -- especially since that will be available on average less than half the time. The RPi boards seem to use around 0.7A at 5V (3.5W),. maybe more or less depending on peripherals, but not under the 0.5W average you might get from the 1.5W (peak?) panel. I'd be looking for a 5-10W panel to keep the system alive. The 50Ah battery is more reasonable, especially if that is 12V and you have an efficient switching regulator to 5V. It might struggle in cloudy weather in winter. (Where is this system? How much sunshine?)

VNC won't add to the consumption.
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mikronauts
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Re: RasPi power usage measurements ALL Models

Sun Nov 02, 2014 5:29 pm

Use a model B+

In my review, I did some power consumption testing, and idling at a desktop, a B+ used about 230mA

http://www.mikronauts.com/raspberry-pi/bplus-review/5/

5V * 0.23A = 1.15W too close to the rated 1.5W to rely on it.

I'd upgrade your solar panel to 6W+, and use it to charge a USB powerbank of at least 12000mAh capacity, and power the Pi from that.

The above numbers assume you want to run your server 24/7
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ReynaldoTrabue
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Re: RasPi power usage measurements ALL Models

Mon Nov 03, 2014 6:36 am

mikronauts wrote:Use a model B+

In my review, I did some power consumption testing, and idling at a desktop, a B+ used about 230mA

http://www.mikronauts.com/raspberry-pi/bplus-review/5/

5V * 0.23A = 1.15W too close to the rated 1.5W to rely on it.


I'd upgrade your solar panels to 6W+, and use it to charge a USB powerbank of at least 12000mAh capacity, and power the Pi from that.

The above numbers assume you want to run your server 24/7
I think you have got good solar power system..There is plenty to learn and even I will upgrade my solar power system now..

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alexeames
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Re: RasPi power usage measurements ALL Models

Wed Nov 12, 2014 2:54 pm

So. New model of Pi, the A+.

New round of power measurements (Vin was 5.2V) :)

Image

I omitted the B as I spent all afternoon on this already. But for sake of comparison, at IDLE CLI the B drew 380 mA when measured against the B+ in the summer (although Vin was a little lower, so not a perfect comparison).

Bottom line. A+ uses about 70% of the power of the model A. Full review including video of the whole process here...
http://raspi.tv/2014/raspberry-pi-a-how ... es-it-need
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TimG
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Re: RasPi power usage measurements ALL Models

Thu Nov 13, 2014 12:09 pm

I don't have an A+ in my hands yet, but I'm hoping for current consumption (at 5V) well below 100mA. My non-plus A draws 93mA in idle with the video switched off (/opt/vc/bin/tvservice -off).

The regulator claims to be 95% efficient so I'm expecting the A+ to draw about 65mA at 5V. Maybe slightly less since there's also a switching regulator for the 1.8V rail.

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alexeames
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Re: RasPi power usage measurements ALL Models

Thu Dec 03, 2015 11:25 am

Update to add Pi2B and Zero
Pi Zero Power Usage Table.jpg
Pi Zero Power Usage Table.jpg (337.02 KiB) Viewed 1430 times
Pi Zero Power Usage Chart.jpg
Pi Zero Power Usage Chart.jpg (295.03 KiB) Viewed 1430 times
Alex Eames RasPi.TV, RasP.iO

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