Power is the ability to supply a device with energy. This question covers how to power the Pi, ways to do it, and the safe ranges of power.

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2
votes
1answer
49 views

Switching power source from power bank to mains without interrupt

I'm planning to build a robot similar to one described here. The pi and the controller are going to be powered from powerbank. However, as big fan of live coding I am (there's gonna be some LISP ...
0
votes
1answer
20 views

Measure SoC (Juice left) in battery

I'm powering my raspberry pi with 2 no-break batteries. I want to know if is there any way for me to know how many percent of the battery is left. If is there anyway to measure it would be great so I ...
1
vote
1answer
53 views

External shutdown (properly) button?

I have a R-Pi that I want to mount in an enclosure. The enclosure already has a couple external buttons on it. I'm trying to find some sort of circuit that I could by that I could wire the buttons to, ...
0
votes
1answer
22 views

Getting 3 new entries in /dev/ttyUSBx for each 3G dongle connected

I am trying to connect 4 3G dongles to Raspberry Pi B+, I have some troubles making them all reply to AT commands, and I see that each time I connect one dongle, 3 new /dev/ttyUSBx ports are created ...
0
votes
3answers
73 views

Detect Power Loss in AC outlet

Hy, I want to make my Raspberry Pi to detect AC power outage and send E-mail/SMS accordingly. The Pi I have is model B not the B+. Now I have read other posts but my request is different. The idea ...
0
votes
0answers
39 views

Trouble connecting Pi to Digital LEDs (_spi_module not found)

I have cut a strip of 4 LEDs from these digital addressable LEDs: https://learn.adafruit.com/digital-led-strip?view=all I have a 5V / 2A power supply (the one recommended) from Adafruit, with a 2.1mm ...
0
votes
1answer
55 views

B vs. B+ power consumption

I've read several comparisons of the Model B vs. B+, and they mention that one of the benefits of the B+ is it has lower power consumption. With the same processor, and most of the same components, ...
1
vote
2answers
207 views

Car computer how to connect to car battery and also not drain battery when the car is switched off

I am doing research on creating a car computer with raspberry pi (so I have all the basics down before I start this project) and I am looking on a way to switch the whole device automatically whenever ...
0
votes
0answers
23 views

How can I schedule a task to power down USB HDD and USB Wifi?

I have a RaspberryPi B+ which I connected to an USB HDD and a USB Wifi adapter. Both works great. Also, I have running a webserver and a seafile server. Now, I want to set up a task (scheduled at ...
0
votes
1answer
33 views

UPS with battery reading

I need a UPS (Uinterrupted power supply) which I can connect via gpio to read if it is charging, the battery level, etc. Anyone know how I can make one or where to buy one from? Thanks
1
vote
1answer
47 views

Turning LED light on with Pi

I am looking to build a home security camera with a LED light attachment. Many people mention they use a IR Illuminator for the light source which often seem to be DC 12V. I am not sure how one would ...
1
vote
1answer
43 views

all raspberry pis connected to same breaker box are having their inputs pulled high or low randomly

I work as a tech guy for an agriculture/tourism farm. I have set up about 60 or so raspberry pis throughout the farm to control lights/props/sound effects/music/video. They are amazing and I have ...
0
votes
2answers
47 views

contact pin 1(3,3v supply) pin 6(0v ground) reboot [closed]

I want to supply a circuit with these two pins. But when they contact each other my raspberry reboot. Is my raspberry broken?
1
vote
1answer
31 views

Measuring current using test points

I understand that one can use the test points on the raspberry pi (model b) to test the voltage on the pi through a multimeter. Can the test points also be used to monitor the current on the board?
1
vote
1answer
56 views

Do 5V/3A External Batteries exists? [closed]

Need one to power my PiHUB so my project gets portable, and I don't need a cable. Unfortunately the battery packs I find on amazon, are 5V/3A ad in: 1 USB 5V/2A, and 1 USB 5V/1A ... so 2+1 = 3A ...
1
vote
1answer
55 views

Portable power supply for a PiHub?

I love my PiHUB and would like to have a or table power source, so I can make my projects mobile :) Is there any product that I could use? It uses 3A 5.2V. Alternatively I'd appreciate any ...
0
votes
2answers
135 views

Powering Raspberry pi with 12 volt input

I am trying popped a transistor while trying to power my raspberry pi from a bread board. I have a 12v battery pack that I am going to use to power my raspberry pi and some servo's. Yesterday I ...
2
votes
2answers
90 views

How long have you run your Raspberry Pi since its inception in 2012 [closed]

I would like to know how long can Raspberry pi be on without turning it off? I am looking for the maximum uptime. It's been 2.5 years since the Raspberry Pi was first launched and I am curious to know ...
0
votes
1answer
535 views

How to switch my Raspberry Pi B+ with OpenElec on and off?

I have a Raspberry Pi B+ set up with OpenElec which I happily use as a media player for movies. What would be the best way to switch it on and off in a similar way I switch my TV or BluRay Player on ...
1
vote
2answers
80 views

Building a remote drone with a pi

I am having trouble with powering my raspberry pi drone. I cant seem to find a battery small enough to let the drone fly but large enough to sustain flight for a decent amount of time. Any ...
0
votes
3answers
80 views

Is it possible to power a raspberry pi using android phone in USB host Mode?

the android phone can be used in USB host mode to power an arduino, pen drive,mouse. Is it possible to use the android phone to power a raspberry pi?
0
votes
1answer
99 views

Using Raspberry Pi to make Internet TV box (Power on/off issue)

I need to make a box (STB), which when plugged into TV can display live streaming URLs and can be controlled from remote control. So that a user can have the same experience as of a traditional live ...
0
votes
0answers
49 views

Pi not recognizing USB ports with an adequate PSU

So I got the Raspberry Pi B+ about 3 weeks ago and it hasn't been functioning 100% correctly... I have a PiHub to power my ehdd (1tb WD Elements), Wifi Adapter Realtek 8188CU, and (usually) the ...
1
vote
0answers
73 views

UPS for raspberry pi

I want to be able to power my pi like a smartphone (ie from battery or from mains (while charging the battery), hot swappable) I know there are boards like the MoPi that achieve this, but the ...
2
votes
2answers
53 views

Should I power my Pi and USB hub through the same power supply or separate ones?

Should I power my Pi and USB hub through the same power supply or separate ones? Because they both run. But which is better for the Pi?
1
vote
2answers
28 views

Unresponsive USB on a Raspi Model A

I've been running a headless Pi Model A (1 USB and no ethernet port) for a little while and it's just stopped working. The wifi dongle shows no life, and the pluggin keyboard has no effect. So I ...
0
votes
2answers
240 views

Reducing 24V to 5V for RPi PSU

I'm trying to power several devices off of a breadboard. For simplicity I want to power these all from the same PSU. The highest voltage amongst the devices is 24V. I was looking to use a 24V 2A ...
0
votes
0answers
40 views

No 'system halted' message when shutting down

I'm using putty to log into my pi through a serial console cable. I entered the command sudo shutdown -h now According to an answer to a previous question on shutting down the pi, I need to wait ...
3
votes
2answers
147 views

How to make Raspberry shutdown when I unplug the ethernet cable

I use my Raspberry Pi Model B with Raspbian as a server and I want to know (if it is possible) how to make that the Raspberry pi send itself a halt command when I unplug the Ethernet cable (eth0) Any ...
4
votes
1answer
102 views

UPS for Raspberry Pi and router (TPLINK TD-W8961) [duplicate]

I have started hosting a website on my raspberry pi, but because of the power outages, and mostly because I'm itching for a DIY project I would like to build a UPS for my pi and my router(12v-1,5A). ...
0
votes
0answers
207 views

Why I blew up my brand new B+

I blew my B+ up in less than 2 days.I want to know what went wrong to prevent it from happening again. What I remember doing: I was making GPIO to run for my RC car(1A motors), I did use TIP122 ...
1
vote
1answer
52 views

Why is pin 5 in the Ethernet connected to 3v3? is it safe to disconnect?

Looking at the pinout of the Pi's Ethernet, it looks like pin 5 is connected to the 3v3. Why is it connected there? According to the 100Base-T Ethernet specification, that should be unconnected. ...
0
votes
0answers
26 views

How much power can a Pi deliver to a SD card?

SD cards (the full-size ones) can use up to 330mW of power (100mA at 3.3V) - The Pi is known for having difficulty with certain high-speed (and thus high-power) cards, so I believe it is less than ...
0
votes
2answers
127 views

Powering a 24V 1A device

I've got a little project going where I want to hook up a load of sensors to my RPi (PH, Temp, Humidity, light etc. etc., a camera, and also power a 24v 1a DC device. I'm wondering if this is ...
0
votes
0answers
48 views

Wvdial and usb_modeswitch dont work unless Device is hotplugged

I want to connect to the internet using a 3g usb dongle. I have downloaded ppp, usb modeswitch and wvdial. Modeswitch is able to switch my from storage to modem only if I hotplug the device into the ...
2
votes
1answer
112 views

Power Pi from Li battery?

I would like to use a 4.2V(voltage varies from 3.6v up to 4.2v) Li battery to power a Pi - for this it seems like I would need a DC-DC boost converter. From what I found, all of those seem to create ...
3
votes
3answers
185 views

Pi Headless: How to confirm that the Pi is shut down

I am running my Pi headless connected to my wireless router using a ethernet cable. I wanted to shut down the pi remotely even when I am not connected to it using SSH/Putty to shut it down ...
0
votes
3answers
153 views

7.2V battery with Raspberry Pi

I want to use a 7.2V (4200mAh) battery with my raspberry pi but I need to convert the output to 5V (2000mAh), I tried the following formula: Ω = V / A but when I try to find the ohms the result ...
1
vote
2answers
81 views

power on from idle with gpio3, undocumented?

reading this thread : http://raspberrypi.stackexchange.com/a/19659/19456 i found out that you can power on the rpi from idle by connecting gpio3 (pin5 revB) to ground, tested it and it works great. ...
0
votes
2answers
85 views

Hot plugging the GPIO cable

I just got a raspberry Pi, and I am more familiar with software than hardware. Can I plug my ribbon cable into the GPIO pins if my Pi is on?
2
votes
1answer
2k views

Maximum current from usb (model b+)

I want to run the ps eye camera for my raspberry pi model b+. It is rated at 5v 500 mA . The question is , is it wise to directly connect it to the provided usb? I am using the pi to make something ...
0
votes
2answers
96 views

Raspi periodically unreachable via SSH

I'm using a RPi Model B as a file server back home. I set it up according to HTG's RPi file server guide, so I'm using SFTP to access the files on it. The RPi is wired to a Linksys router functioning ...
4
votes
2answers
392 views

What power supply should be used for the B+ model?

So I'm thinking about purchasing a RPi B+ model, and the Pi website states that the power supply should output 2A through a Micro USB supply. OK, but in terms of volts what should it be? Is 5V ...
5
votes
5answers
2k views

Why do people use powered usb hubs?

I have the RPi B+. It has four usb ports. At the moment I am powering an Arduino Mega, a small RFID reader and a keyboard. I plan to also power a wifi dongle and an arduino uno. Will this just work? ...
0
votes
2answers
91 views

Using a Generic Switching Power Supply

I have a generic 5V 10A switching power supply with screw terminals, that looks kind-of like this: Is it safe to use the output from here to drive the Pi by cutting a USB cable and connecting the ...
1
vote
2answers
88 views

Mult-head micro-usb cable

I am building a raspberry pi cluster. I am looking for a multi-head micro-usb power cable to power them. Does such a beast exist? Or can I make one myself?
0
votes
2answers
276 views

Is it fine to use an ASUS Memo Pad power supply on a B+ RPi?

I'm about to make my first RPi purchase (a B+) to be specific. I do not want to spend any more than I need to, and hence have looked around to see what power supplies I have that may already work with ...
0
votes
2answers
112 views

Raspberry unbootable after unexpected shutdown

I have a raspberry Pi, Model B. I installed Raspbian on the SD card and I would like to use it as a SVN server. The problem is that when it shuts down unexpectedly (i.e. there is a blackout, or DC ...
0
votes
0answers
116 views

Powering 3.5 inch LCD screen and RPi with 7.4V Lithium Polymer Battery

I am attempting to create a portable Raspberry Pi. I am wondering how I would go about running the RPi and the LCD screen from the same battery. The screen draws about 6.5V. I have a 5V voltage ...
0
votes
0answers
50 views

Raspi not 'accepting' JUH340 USB Hub. (Raspbian OS)

Easily, not too many people have asked a question about this model of usb hub. What I'm attempting to use is a J5 CREATE JUH340 USB 3.0 with the RPi, but it is highly unworkable. With most everything ...