Hot answers tagged

29

You can perform a Raspberry PI stresstest with the sysbench tool. First example calculate primes sysbench --test=cpu --cpu-max-prime=20000 run Second example test the I/O Output of your Raspberry Pi sysbench --test=fileio --file-total-size=2G prepare sysbench --test=fileio --file-total-size=2G --file-test-mode=rndrw --init-rng=on --max-time=300 --max-...


28

Short answer Yes, most (but not all!) USB power banks are capable of powering a Raspberry Pi, since they usually have an output voltage of 5 V. And yes, by using a (quite large) 50 Ah power bank, you can definitely expect your Pi to run for at least 24 h. See the long answer below for reasoning and further relevant aspects. Long answer According to actual ...


20

The Pi has no inbuilt current or voltage sensors which could be used for monitoring its own current draw, or a battery supply. You will need to track down a multimeter or other measuring device (this type of thing is very common) to keep track of your power consumption.


17

The Pi 3, while idling, consumes about 220 mA. Under loads, it is known to reach up to 1 A, and with USB devices plugged in, it can reach 2.5 A. There is no on board current sensor, so this is only a tool for a good estimate.


15

I wrote the little command-line tool stressberry the other day which stresses your Raspberry, measures the core temperature, and produces nice plots. Install with pip install stressberry --user and run with stressberry-run out.dat stressberry-plot out.dat -o out.png


14

I took a quick look at some light and powerful lithium polymer batteries, and it looks to me like a battery similar in scale to the Zero is not going to provide much capacity. Let's keep in mind that the computer only weighs 9 g. A LiPo of similar size [1] contains a about 1.3 W*h of energy, which won't power the Pi Zero for a full 3 hours, even idle. [2] To ...


13

vcgencmd will show the internal voltages for core, sdram_c, sdram_i, and sdram_p: vcgencmd measure_volts core The output will look something like this: volt=1.20V The following shell commands will display all the voltages: for id in core sdram_c sdram_i sdram_p do echo -e "$id:\t$(vcgencmd measure_volts $id)" done


12

Absolutely DO NOT connect the battery in parallel with the load. The charger will not know if the battery is full or not and will continue to pump power both to the battery and the step-up converter. Since the battery is still receiving power and is still charging, it will overcharge and explode. If you want to do this properly, you should use a proper ...


10

you'll need some external circuitry to do that, because afaik the raspberry does not provide the battery voltage anywhere in the system: http://raspi.tv/tag/raspberry-pi-monitoring-its-own-battery-voltage


10

For the CPU and most other things you can use nice -19 stress-ng -c 4 --metrics --timeout 60s For the GPU they suggest GeeXLab at geeks3d.com.


10

The pi can't draw more than 1A due to a fuse stopping the board drawing more than that. So how big a battery you need really depends on how long you want it to run. If you have a 500mAh battery, that will output 500mA (0.5A) for one hour, or 1000mA (1A) for half an hour. Similarly, a 2000mAh battery will give you 2000mA (2A) for one hour or 1000mA (1A for ...


10

As long as the power bank outputs 5V it will power the Pi. It claims 50000mAh so it claims 2.5 amps per hour for 24 hours. Assume it will deliver half that so 1.25 amps for 24 hours. If that is enough or not will depend on what you have connected and what the Pi is doing.


9

Yes, should do Just double checking the datasheet of the MT3608: if using AA rechargables instead of batteries, mind the lower voltage (cell voltage 1.2 V), but for two cells in series still above the lower lockout voltage (2 V) of the MT3608 at very low input voltages the efficiency could be lower than 80 %, the datasheet (p. 5) lists 80 % at 3 V and a ...


8

Either would power the pi and your peripherals. The pi could draw between 0.5A and 1A (depending what camera and how much wifi), so the 4Ah battery should last 4 to 8 hours and the 10Ah battery 10 to 20 hours. Choose the one which gives you the duration you want, or a smaller or larger as required. A standard 9V non-rechargeable PP3 has a high internal ...


8

9V battery has about 500mAh, since your Pi consumes about 700mA, you're looking at run times about 40 minutes, more or less depending on the type of the battery (a good quality panasonic industrial type has 570 mAh.. low end type probably more like 400). running Pi with 9V battery and a linear voltage regulator is very inefficient, you basically turn almost ...


8

This will NOT work. You cannot just use a resistor. If you try you will destroy your Pi. You will need a regulator. A switching regulator is recommended.


8

The batteries won't force current through the system. Your bigger problem, though, will be running the Raspberry Pi 2 at all on 4.8 V. It's very close to under-voltage warning (which I saw quoted as 4.65V for the B+). You'll need some kind of DC-DC converter to get the voltage to consistently ≥5V.


8

You can use: A USB battery pack like this one from Adafruit. Others have used powerbanks like this one these allow charging the battery and powering the Pi simultaneously (more info on using these can be found here). You could use 6 AA rechargeables (this may require additional components). A desktop UPS (this will be significantly bigger than the other ...


8

Intro: Many of my contributions to this forum have centered around innovative ways to power a Pi which is awkwardly out of reach of a mains socket, specifically using POE. But what do you do if there's no mains power source at all, ie: Pi used in off-grid conditions or mobile use where the Pi is not stationary? As the Pi 4 now had a USB-C Power socket, I ...


7

The problem was that there was no ground between the L298N and the Raspberry Pi. By wiring the Ground (-'ve) terminal on the L298N to a ground pin on the Raspberry (as well as the batteries) it then worked.


6

In the scenario of a USB power pack, you'd have to add a circuit to the Pi that monitored its own voltage, e.g. through an ADC (analogue-to-digital converter). This would give you the capability to estimate when battery was low enough to trigger the internal power pack cut-off. A simple service running in the background would check the voltage every few ...


5

It outputs current at 800 ma/h I think this measurement/units are wrong. Amps are defined as Coulombs/s. So your current cannot be 800 mA/h. Your output current is 800mA. You can give a measure of the energy hours stored in the battery using a unit like A*h. But I digress... What matters here is the output current, I think as long as you're close to 1Amp ...


5

Rechargeable powerbanks are great for this. They are made to recharge mobile phones, so they have standard USB output. I use them in a few of my projects with different Raspberry Pis including the Zero. The size really depends on how long you need it to stay on battery power. For reference, the Zero uses about 200mA max, so if you want it to run for 10 hours,...


4

you cannot, unless you're ready to solder some external ADC converters to I2C or serial and write scripts that will read the data. there are NO embedded ADC converters on Raspberry Pi.


4

XBMC doing multimedia decoding might be a good test as well as the UI there is in OpenGL. A game that constantly hammers the frame buffer (memory!) while including a numerical simulation like OpenTTD is also a pretty good test. The generic Dhrystone and Whetstone benchmarks might also be good. There's an OpenGL game I'm working on porting called Armagetron ...


4

It may be marginal, you'll have to try and see. You won't damage the Pi (at worst if the power is insufficient you might corrupt an SD card). http://www.raspberrypi.org/help/faqs/#powerReqs


4

You could build a boost converter using a TPS61030 boost converter from TI or you could use this product that uses it. Personally I would be nervous using a cheap converter from ebay to power my RPi.


4

Sources on the Raspberry Pi forums say the Raspberry Pi uses approximately 500mA add in the 250mA for the camera module, and round for a safety margin equals approximately 1A. A 50,000mAh battery will run 1A for 50 hours. Even with additional safety margin that is plenty to run for 24 hours.


4

Something to keep in mind is that some power packs will shut themselves down if there isn't enough of a power draw. For example, I have a New Trent PowerPak+ 13500mAH power pack, which shuts itself off after a couple minutes if it's only powering an Arduino or Raspberry Pi. (Plugging in my hungry smart phone prevents this) Any USB power pack will certainly ...


4

Short answer, yes it will work great. For some more info: "The device is powered by 5v micro USB. Exactly how much current (mA) the Raspberry Pi requires is dependent on what you hook up to it. We have found that purchasing a 1.2A (1200mA) power supply from a reputable retailer will provide you with ample power to run your Raspberry Pi for most applications,...


Only top voted, non community-wiki answers of a minimum length are eligible