Which one is the standard? There are at least 52 sizes to choose from. Barrel jacks are also bigger the USB µB, so wouldn't fit in existing cases.
Unless you have the good sense to buy the official 5.1V 2.5A PSU with bult-in 18AWG cable, or any of the other supplier's near-equivalents.
Me not joining discussions about Micro USB for powering so just providing this bit of information related to somewhat 'popular' SBC:
What happens when a reversed polarity 24VDC 3A adapter is plugged into the Odroid's barrel connector?
Well there was at least one "USB-device" barrel power supply with negative polarity: http://www.cpmspectrepi.uk/raspberry_pi ... .0V.22_PSU (Ironically one of the "better" PSU's of its type I've tested w.r.t. "current loading" effects.) Some, now quite old, hubs incorporated their own regulators and were powered, again by barrel jack, from 6V: http://www.cpmspectrepi.uk/raspberry_pi ... ubPSU.html andPaul Hutch wrote: ↑Sat Mar 17, 2018 5:19 pmWhat happens when a reversed polarity 24VDC 3A adapter is plugged into the Odroid's barrel connector?
My guess is it releases the magic smoke.
That's the beauty of using the the USB microB standard, there is virtually* no power adapter around that will damage the Pi. The adapter may not allow the Pi to operate correctly due to low voltage but it won't release the magic smoke from the Pi. Not letting out the magic smoke is essential for a device designed to be used in children's education.
* I say virtually because there is probably some bozo somewhere who made a custom unit with more that 5.25V or reversed polarity with a microB connector.
If you're drawing 1.8A from the wall--in the US that would be 210vA, or just under 150W--something is seriously wrong. (Approximately double those figures for the UK.) The max rating for any Pi is--IIRC--2.4A @ 5.2v, or about 12.5W.
Ah hemm... that would be me.* I say virtually because there is probably some bozo somewhere who made a custom unit with more that 5.25V
You're right, I don't have 22 AWG micro-USB cables. I have 23, 20 and even 19 AWG micro-USB cables which all work great with Pi Computers.
Likewise, this evening. Did an update/dist-upgrade cycle earlier today and simply shutdown, disconnected, swapped in the Pi3B+ (in place of the Pi3B I've been using), reconnected everything and the Pi3B+ booted right up...from a PiDrive. Probably the fastest boot of a new Pi from box opening to running system I've ever done.
That's good. None of them are standard, don't use any of themImperf3kt wrote: If someone could please instruct me on which is the "standard", I'll start using it right away!
Got so wrapped up asking which of my (small selection) of barrel connections was standard that I forgot to ask if this person you speak of was using an adequate power supply?
My bad, misunderstanding. I was translating to the current drawn at 5V. I've never seen any of my Pi 3 exceeding 9W at the wall (5V @ 1.8A) since all the time then frequency capping occured.
Seems this got better with the new board but still... Micro USB is rated for 1.8A max anyway. And why do people focus on amperage ratings (or are told to do so) when the problem usually is the voltage drop?While running these benchmarks, we noticed significant deficiencies of the Raspberry Pi 3 Model B. At first we thought it was our specific board but it was repeatable on every Raspberry Pi 3 Model B we purchased. Using a programmable DC power supply set for 5.1V was not sufficient to prevent the nasty rainbow square issue at full load. The polyfuse on the Raspberry Pi 3 experienced unexpectedly high voltage drop at just 1.5A. This caused huge inconsistencies in its benchmark results until we determined the cause. We had to drive the MicroUSB plug at 5.55V in order for it to achieve the necessary voltage levels on the 5V rails to prevent firmware clock throttling at full load.
Excellent. Your muddle headedness is preserved for all to see, forever. And you have brought it to our attentionFor the censors/moderators: it's stupid to delete my post
Do you have a link to this project. Surely anyone building such a thing would write it up some place. Especially if they are a "fanboy". In fact, with such a high failure rate I would expect that they popped up here to complain in person. Where are they? I'm sure whatever issue that they had getting power to those Pi could be addressed.I know of one specific Pi fanboy who ran a 48 node RPi 3 cluster. 9 of his nodes were able to run at 1200 MHz while all the other where frequency capped and limited to 600 MHz.
Nope, I tried to explain the problems associated with the various barrel plugs that are used and already said that I would be happy getting USB-C since this standard unlike Micro USB has been designed thoughtfully.
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People focus on the current and not the voltage, because the current matters, not the voltage. the only thing you need to worry about with voltage is not exceeding 5.25v at the power input and not dipping below ~3.4v at the GPIO 5v header.
Unfortunately this is related to battery charging and not the maximum currrent the port/receptacle can carry - as can be proven just a few lines later:Battery Charging Specification 1.1: Released in March 2007 and updated on 15 April 2009.
Adds support for dedicated chargers (power supplies with USB connectors), host chargers (USB hosts that can act as chargers) and the No Dead Battery provision, which allows devices to temporarily draw 100 mA current after they have been attached. If a USB device is connected to a dedicated charger, maximum current drawn by the device may be as high as 1.8 A. (This document is distributed with the USB 3.0 and USB On-The-Go. specification packages)
It is also talking about USB A, not Micro B.Battery Charging Specification 1.2: Released in December 2010.
Several changes and increasing limits including allowing 1.5 A on charging ports for unconfigured devices, allowing High Speed communication while having a current up to 1.5 A and allowing a maximum current of 5 A.
Funny. What was the maximum consumption you've ever seen when using an RPi? More than 9W?