That God %$#@ Lightning Bolt
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@rbaker said in That God %$#@ Lightning Bolt:
@markwkidd said in That God %$#@ Lightning Bolt:
Do you have a citation on this?
Thanks! So we have manufacturers skimping on copper and violating the USB spec by reducing wire gauge.
From what I'm reading there, it's still no reason to avoid one style of power supply over another. Just like controllers, cases, and anything else that's mass produced there are bogus cables out there. Source one from a reliable vendor or take chances with knockoff or out of spec gear.
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@clippercm I agree! I'm also not a fan of the whole USB connectors used for power on the Pi's. In the USB 1.0 and 2.0 specs, a standard downstream port is capable of delivering up to 500mA (0.5A); with USB 3.0, it moves up to 900mA (0.9A). I wish they would have gone to a barrel power connector like most laptops use.
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@markwkidd yeah AliExpress is a terrible source for proper usb cables. My hub was proper but anytime the USB was plugged automatic lightning bolt.
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If you have a couple multimeters (or a o-scope better yet) connect them to the output of the power source and look to see if the current is limited and tops out at a certain number or see if you get voltage drops when a load kicks in. I’m guessing cheap cables are the culprit, badly made cables made of cheap materials can act as an electrical shunt and cause unwanted resistance.
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I cracked open a 2a power supply that I bought for my pi2 from some chinese website for like $5 a few yrs back because it was giving my pi2 the lightning bolt which it never had before. The wires from the plugs to the pcb were really thin and over time, because the way they got shoved in, the wires were getting loose. I replaced them with the thick kind from a dead pc power supply and it works again.
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Corrupt Install after reboot
I seem to have a problem with this version of the RPi, RPi3B. It seems that it is a beast of an energy hog where it needs a specific power supply that does not come with it. YES, I get the lightning bolt from hell. After using 6 different USB power supplies I still get the same problem. Did someone give RPiorg the specs of USB power?
As I had mentioned above that I had used 6 different USB power supplies. 3 were rated at 2.1 Amps, 1 at 4.8 Amps, 1 at 850 MilliAmps and a portable power bank with a rated output at 1 Amp.
The 3 different USB power supplys(ASUS, STAPLES and RADIOSHACK) that were rated at 2.1 Amps were 120volt mains plugs for charging cell phones. Using a "USB Doctor" and seeing the voltage from 4.8 to 4.9 and the current draw from 230-300 MilliAmps.
The 1 USB power supply(blackweb) that was rated at 4.8 Amps(I would not recommend this) is a mains plug with 2 USB power outlets. Using a "USB Doctor" and seeing the voltage at 4.8 and the current draw from 230-300 MilliAmps.
The 1 USB power supply(RIM branded Blackberry charger) that was rated at 850 MilliAmps is a mains plug with 1 USB power outlet. Using a "USB Doctor" and seeing the voltage at 4.8 and the current draw from 230-300 MilliAmps.
The portable power bank(Circuit City/NEXXTECH) with a rated output at 1 Amp was the worst with using a "USB Doctor" and seeing the voltage at 4.7 and the current draw about 500 MilliAmps.
After installing retropie on the same LEXAR 16GB MicroSD about 10 times to run on my RaspberryPi 3B. I gave up to come here to see if there is a soft hack to fix this problem of corrupted intalls. I am able to copy the retropie image version 4.4(I had tried 4.2 and 4.3 as well) to the 16GB MicroSD card and it will boot the RPi 3B into the kernal where I am able to update and transfer files and play the games that I loaded onto it. It looks like it shuts down properly when I select the menu option to shut down. When I try to reboot, the RPi 3B does not want to boot up again.
Understanding what is going on here is the Lightning bolt effect(error). Yes I do see a lightning bolt show up but that is half of the problem. The other half is the system halts itself when it detects the power is low. Is this causing the corrupted installs that I've been suffering?
I had used a different distro named OSMC and installed without any trouble and rebooted many times without any corrupted install.
Is there a way to hard-write the RPi 3B to only complain of the voltage if it sees it below 4.5 volts? Is there a way to stop the system being halted on low-voltage errors?
Buying a 2.5 Amp RPi-Certified power supply is NOT an option if this is the case because it should be included with every single RPi that was sold. Some people are actually having trouble with the RPi-Certified Power supplies not supplying a proper voltage. Just wondering if there is a decent fix for this problem.
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@unrealduke So, in spite of the specs put up by the Raspberry PI team and their recommendations, you try a lot of chargers/power sources that are clearly out of spec, then you experience sd corruption and system shutdown because of it and then you still try to find a software solution because you bought your PI without a proper power source ?
Get a proper power adapter, it's the only option. -
@mitu, Show me a spec sheet that demands at least 5.2 volts for each piece of silicon on that circuit board. Did you even check the current draw ratings that I posted?
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@unrealduke https://www.raspberrypi.org/documentation/hardware/raspberrypi/power/README.md
The recommendation and the official power supply is 5.1V 2.5A. So buying anything below is a waste of time. Though, 5.1V is the required voltage. Amps can vary but must be at least 2.5A or higher. There is no reason to buy 1amp stuff. I bought the official pi power supply and have no regrets.
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@all Show me a spec sheet that demands at least 5.2 volts for each piece of silicon on that circuit board.
Honestly, this thing was is supposed to be USB powered. I probably have the exact same quad-core CPU in my cellphone running off of a 3.8 volt Lithium-Ion battery.
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@unrealduke This link has all you need with regard to current draw . Can't believe you are randomly trying "chargers". Chargers will never work because they are designed to charge - most cannot cope with maintaining a stable voltage under load.
You then say "The 1 USB power supply(blackweb) that was rated at 4.8 Amps(I would not recommend this) is a mains plug with 2 USB power outlets. Using a "USB Doctor" and seeing the voltage at 4.8 and the current draw from 230-300 MilliAmps." Now are you talking 4.8 amps? or 4.8volts? you appear confused and are mixing the two.
You need a power supply capable of holding a constant 5.1V at greater than or equal to 2.5A. You will never see the lightning bolt anymore.
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@rbaker,
"Now are you talking 4.8 amps? or 4.8volts? you appear confused and are mixing the two."
Kinda BOTH! The power supply is rated at 4.8 Amps and while in use with the RPi the voltage was at 4.8 Volts and drawing 230-300 MilliAmps.
We are talking about USB standards. Here's a link. https://en.wikipedia.org/wiki/USB#Power_related_specifications
I should be easily able to power the RPi with at least 4.75 Volts without trouble. The "Designers" of it should have used a different power connector. -
@unrealduke As it was already mentioned by @rbaker , that is a charger. It's not good enough for the pi. The problem here is user error. Chargers can't constantly output that power. You need to purchase a 5.1v 2.5A or higher POWER SUPPLY. It's easier to know what you're getting if the packaging says it's meant for the pi.
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@darksavior, Then we are talking about a type C connector that will handle the amperage above the 1.5 Amps. but maintain the 5(5.1+) Volts... USB Standard Voltage is at 5 Volts with 5% Tolerance. 4.8 Volts is within spec. Why even bother to use a Micro B USB connector in the first place if it is supposed to draw more? I am not the one who should answer that one. RPi's are designed to use USB power.
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@unrealduke said in That God %$#@ Lightning Bolt:
RPi's are designed to use USB power
Not true, they are designed to use a micro USB connector to receive power!
I should be easily able to power the RPi with at least 4.75 Volts without trouble
Why do you think this?, it is just not true, especially if you are using a charger. It may boot but when you try to draw current from that, the voltage collapses and so does your Pi. A power supply is regulated - this is a very important concept to understand. In my cabinet builds, I use boxed regulated power supplies similar to those found in PCs but smaller. With those, you can power all sorts of other stuff together with your Pi. RGB LEDs for example. Then there is the whole USB cabling issue - choose a poor one and it will fail to deliver the required power even WITH the correct specifications.
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@unrealduke Take a look at this for an example. You can wire these up to a build with your own wire and they are rock solid. That said, I have no issues with the official PSU with an Ipac, keyboard and two controllers connected at once with an LED Marquee. I have had issues with a dedicated usb power supply rated at 3A. Each socket was not capable of delivering the minimum spec. It's obvious use would be to charge three things at once like a headset, a phone and a camera. I think this is the issue you are facing. A typical USB 2 port will source a maximum of 500mA and a USB 3 port around 900mA. Some dedicated charging ports source about 1.5A which gives a false sense of security as your hardware appears to work until you stress it. All are inadequate regardless of the rated voltage.
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@unrealduke Finally, there is a script that I saw on here quite a while ago. It disables the power restrictions. I have not tested it and when disabling things like this, you should be cautious as these are in place to preserve your pi over time. Anyway, you can take a look here.
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If you know anything about building electronic circuits you'll know that there are hundreds of difference schematics of varying quality for any given task.
You can make a 5v power supply from 2 diodes, an LM317 with 2 electrolytic caps, 3 resistors, a potentiometer and a breadboard... or you can make a 5v power supply from a 4 diode bridge rectifier, noise reducing ceramic caps in parallel with electrolytic filter caps, dropout and linear voltage regulator ICs and a host of other components.
Both will show 5v on the output rails when you connect a multimeter, but the cheaper supply may have voltage drops and spikes ranging in the milli to nano second range, signal noise or a host of other problems.
When you get a cheap supply (aka charger), it's cheap for a reason, the builders cut corners and did the bare minimum to get the "required" output into spec . Phone chargers do not need to hold consistent cc/cv since batteries have wide voltage tolerance, sensitive electronics relying on clean power and cv will not fare so well.
The only way to accurately check the quality of a power supply is to connect it to the pi, power it up and check the test pads (+pp7, -pp6 on a pi 3) on the bottom of the pi with a scope and view the spikes and dips in voltage when the pi draws a load. A multimeter is too slow to show voltage differences in the milli/nano second ranges, but a decent scope will show you just how crappy that mystery wall wart from Goodwill really is.
To put it simply, you get what you pay for.
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Let's see how cheap these things really are...
Interesting enough they are rated at 5 volts. -
@unrealduke Canakit are decent supplies. If youre getting a lightning bolt from a those, then theres something wrong with your setup. Too many connections to the GPIO, power hungry usb adapters or just a bad pi board.
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