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I got a Raspberry Pi Model B+ for the first time and I have been searching in my house phone chargers that I can use. In the manual in the package it stated that the maximum current is 1500-2000mA and the maximum voltage is 5.0v for model B+ I found a charger that has 1.2A and 5v the other one is 2.0 and 5.5v which charger should I use?

-Update I have used the charger with the 1.2A and 5.0v. It works as people predicted and there seems to be nothing wrong. When the RPi is in the terminal, checking the peripherals it looks like everything is a' okay. Thank you fellow individuals for helping me with this problem.

  • I bought a Raspberry pi B+ , instruction paper present in the box says 5V and minimum of 600 to 1800mA. so can i use my 5V and 1000mA adapter ? – parthi82 Dec 17 '14 at 17:12
  • I am guessing you can since the minimum current is 600mA to 1800mA and 5.0v you are right in range. – Bob Wright Dec 17 '14 at 17:28
  • It should do and will not do any harm to try. At worse the Pi will reboot if it isn't given enough power. The B+ uses less power than the B. Any problems will probably happen if you use power hungry items in the USB slots (solution being to use a powered USB hub). – joan Dec 17 '14 at 17:41
  • @parthi82 Welcome :) Since what you posted isn't an answer, it and the responses have been moved to a comment on the actual question, above. Please take the tour if you aren't familiar with how Stack Exchange sites work. P.S. I am sure that adapter will power the pi, although you won't have much left over to power too many hungry USB peripherals. – goldilocks Dec 17 '14 at 19:19
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    @joan you may not use "reboot" and "no harm" within the same commend. reboot on power drop is a proven way to get a corrupt SD card. – lenik Dec 18 '14 at 10:54
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you should use neither. one has too high voltage (5.5V is well over allowed max 5.25V), the other does not have enough current (recommended is 2A, not 1.2A, and it's very likely to throw the voltage far below 5V when used at high current rating).

looks like a time for shopping, you should get the power supply (preferably NOT a cheap phone charger), that provides constant 5V (sharp!) with 2A as a MINIMUM rating (3A, 6A, 10A and 150A are fine, 1.2A is not).

  • If may I ask another question, I actually first tried the low amperage. The RPi's LED actually glowed. The power LED is red, is that a good indication of power? – Bob Wright Dec 17 '14 at 15:31
  • @Bob I think the B+ has a "brown out detector" and will shut off if voltage drops below 4.6 V. – goldilocks Dec 17 '14 at 15:42
  • This would actually be a comment on the lenik's answer, but I cannot comment yet, so here it is: the minimum power requirement is not 2A, it is 0.6A, see here: raspberrypi.org/help/faqs/#powerReqs . 2A is actually the max the Pi can consume. I have at the moment 3 Pi's working in my house all being powered by those cheap mobile phone chargers ranging from 1A to 1.5A. The 1A powered one uses camera, usb WiFi, keyboard and mouse. So don't overrate the quality of the power source you need for the Pi, 1.2A is good enough unless you start adding too many usb devices of use too many o – Lao Dec 17 '14 at 22:18
  • @lenik I agree with your comment about the 5.5v but the other is rubbish. I have been running a B and B+ from an Apple 5W charger (i.e. 1A) with no problems. Most users will have no problems unless they are trying to use USB hard disks. – Milliways Dec 17 '14 at 22:21
  • @Milliways Apple chargers are known for the high quality, try running anything off el-cheapo brand "no-name" chinese charger and you'd be lucky to get 4.5V at the upper current rate. you may check the article ppumpkin wrote on this subject to enlighten yourself. – lenik Dec 18 '14 at 10:58
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The 5V charger has the virtue of claiming to be within the specified 4.75-5.25 volt range so that's the one to use.

It's best to use a meter and actually measure the voltage in situ if possible. The claimed specs may not be realistic.

  • And how do you take measurements in a micro USB exactly? Thanks in advance. – Bob Wright Dec 17 '14 at 15:01
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    @Bob I'd measure between a 5V and a ground pin on the expansion header. Of course you have to take care not to short any pins together. I use male/female jumper leads, female over the pins and use the meter on the well separated male ends. – joan Dec 17 '14 at 15:37
  • @Bob raspberrypi.org/documentation/hardware/raspberrypi/power/… is the B power supply suggestions. A B+ is more efficient and uses less power. – joan Dec 17 '14 at 15:50

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