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82

My research began with the original thread on the Raspi forums: http://www.raspberrypi.org/phpBB3/viewtopic.php?f=63&t=6050&p=291334&hilit=watts+power#p291334 To summarize what we've learned there, the total consumption of a Raspberry Pi is probably not more than: 4 W * 24 h = 96 Wh (I guess that's 346 kJ) (note this is an energy value, not ...


40

It seems that the only concern is that your power supply, if it's not a decent, reliable supply capable of 2A+ of clean output power, might not be able to power the Pi sufficiently, resulting in crashes or frequent rainbows. See, specifically: All that max_usb_current=1 does is to set GPIO38 high, which in turn turns on a FET, which connects a second 39K ...


31

Modern power buttons use the Advanced Configuration and Power Interface (ACPI) to request the OS to turn its motherboard off. That's why, for a couple decades now, if you really want the motherboard off and the OS refuses, you had to mash its power button for several seconds. A simple power switch, like a light switch, could de-power the CPU just when it's ...


30

The ATMega chips specify Operating Voltage: ̶ 1.8 - 5.5V. If you read deeper the operating speed is dependent on voltage. They work at 3.3V but you have to limit the clock speed. The Arduino team presumably chose 5V because of the ready availability of systems which use this (a legacy of TTL). The SOC used on Pi run on 3.3V (and also require a couple of ...


29

I've had a look at the schematic; the data pins for the micro USB connection are not connected to anything. Therefore, there is no way to mount the RPi as an external device. It could be possible to mount the RPi's hard drive or login over the network by using SSH. The GPIO pins include a set of UART data lines, which could be used to form a serial ...


29

There's a short piece that includes Pi 3 benchmarks over at the PiMoroni blog. All of the benchmarks below were carried out with just a USB keyboard and mouse connected with power supplied from the official Raspberry Pi Power Supply, with the exception of the WiFi dongle test in which the USB WiFi dongle was also connected. The Pis were naked, i.e. ...


28

Based on the measurements made by RaspiTV, here are some estimates: 100 mA: No peripherals connected, WiFi And Bluetooth off 160 mA: Bluetooth turned on 170 mA: WiFi turned on 230 mA: Camera connected and capturing Overall, using WiFi and accounting for the 5V power adapter, you are only looking at 1.1 Watts.


27

When shutting down the HDMI and USB on the Pi3, the current drops to 160 milliAmps. In my tests, this was roughly 200 milliAmps on the Pi2. Thus, shutting down hardware (if you don't need it), can be a huge energy saver. Update: Use this command to turn HDMI off: /opt/vc/bin/tvservice -o And this command to turn it on: /opt/vc/bin/tvservice -p Use this ...


26

No, you should not increase the voltage any further... and at least this answer linked in the question does not suggest to do that. From Raspberry Pi Power Limitations: Power sources SHOULD provide 5±0.25V ... and: The newer Pi(3/2/B+) have a voltage monitor chip (APX803) which triggers at 4.63±0.07V. The Pi3B+ uses a MxL7704 chip to manage power, ...


24

Go to a hobby store (or DX.com) and buy a BEC (battery eliminator circuit) intended for model aircraft. $5 gets you a very efficient switch mode voltage regulator, good for around 3A. I use these with all my Pis. Here is an example: http://dx.com/p/hobbywing-5v-6v-3a-switch-mode-ultimate-bec-ubec-15149


23

I don't make a habit of unplugging the pi in the sense of eschewing shutting them down properly except when I've lost networking on a headless pi, in which case I am usually too lazy to plug in a keyboard, etc. Generally I always check to make sure the green ACT light is not on at that point; for recent models (or firmware?) this will be off when the SD ...


22

If you don't want to click links, the Raspberry Pi can handle 4.75v to 5.25v. As for the current draw/power consumption, here are some numbers: All of these are bare-bone (does not have any peripherals/accessories attached) *** Fun Fact (Tested on Pi1 B+) *** Any turned-off Raspberry Pi that's still plugged in: 75 mA *** Idle *** Raspberry Pi 2 B: ...


21

I assume you're talking about using the Pi for digital signage purposes. For the last years we have deployed hundreds of Pi's doing exactly that. Many of our Pi's are not as lucky as yours: they're not on UPS and/or are on 'dirty' power lines. Lost phases, powercuts and power surge peaks are common. Roughly calculated we have about 1% failure - totally ...


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.


18

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 ...


18

You are not doing anything wrong. The activity LED should flash 3 or 4 times just before power off. It is then safe to remove the power. I typically shut-down, go away for a few minutes, and then yank the power cord out.


16

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.


16

The MAXIMUM is 5.25V, although this should NOT be the target. You should not apply more than 5.1V That is not to say the Pi will be damaged by the higher voltage, because nothing uses 5V - the on-board regulator supplies the voltages used by the Pi. There is a point when the transient protection diode will trigger - causing the poly fuse to blow. No one ...


15

You do not need to remove power to restart Pi. There are a pair of pads near the SD Card (I think labelled reset possibly run - I can't see on my Pi because they all have switch soldered on the board.) Momentarily short to restart. Recent Rasbpian have an in-built process for shutdown (handled by systemd-logind) Add the following to /boot/config.txt ...


15

tvservice is not the best to turn off and on the screen. Much better way to do this (found after a day of searching) is using vcgencmd command (more on this here). vcgencmd display_power 0 turns off the screen vcgencmd display_power 1 turns on the screen This allows the Qt application to be visible on the screen after turning it off and back on.


15

I've made this answer to summarize the experience to this issue. We are talking about Raspberry Pi 3 Model B+, released on 2018-03-14. It has some new and updated features compared to Raspberry Pi 3 Model B. A 1.4GHz 64-bit quad-core ARM Cortex-A53 CPU Dual-band 802.11ac wireless LAN and Bluetooth 4.2 Faster Ethernet (Gigabit Ethernet over USB 2.0), maximum ...


14

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 ...


13

Your best bet is to use a USB voltmeter/ammeter between your USB power source and the Pi. 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 ...


12

The HC-SR04 can only be run with 5v(scroll down to specs). However, you can easily fix your problem if you have a breadboard. Assign one row as the 5v "rail" and attach as many sensors as needed. EDIT: How to use breadboard. Basically, the two long rows on the each side of the board can be used as rails for power supply. Just make sure you keep your 5v rail ...


12

If you want to do it with a shell script, here is a solution that works on Pi 1, 2 & 3 (not tested in zero). With the command: /opt/vc/bin/vcgencmd get_throttled If the answer is: throttled=0x0 You're good with the supplied voltage and SoC temperature. The bits on the returned number mean: 0: under-voltage 1: arm frequency capped 2: currently ...


11

Yes, every electronics degrades while it ages, if connected on some power source. The "problem" lies in electronic characteristics itself. One of the phenomena is called electromigration, where IC (actually whole PCB) degrades under various "nonideal" (i.e. working) conditions: current, time, temperature (which is also consequently caused by resistance ...


11

It's NOT an "end-consumer" device, like an Apple TV or a DVR or a microwave. By analogy If you buy a car you expect it to come with door locks... Yes, but you know the manufacturer does not provide those for free, which is why specific price tags are attached to specific goods. If I buy a car chassis, I may not expect locks. Of course, most people do ...


11

Short answer is "Because that's the way it is designed". A somewhat longer answer is "They didn't make it 5V tolerant because it would be expensive". Nobody really mass-produces 5V peripherals anymore (including USB, which has 3.3V data lines). Making 5V tolerant IO pins would make the chip more expensive, and probably a bit slower, while adding close to ...


10

It probably won't damage the RPi, but it may cause random crashes. Depends on many factors. Power supply, other periperals, cpu load etc. The main polyfuse is evil. If the current is on the high side it could trip after a few hours even if nothing else changes I don't power mine through the polyfuse anymore. Much more reliable.


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.


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