rainbow square with 5,17v and a current limit at 30Amps

[flintec]

hello i have read that the annoying rainbow square in the upper right corner on rasp is cause of a weak power supply.
first i used a sellphone charger as powersupply and thats not wierd if its to weak but now im using a PC power supply with 30Amps as current limit and the stupid rainbow square is still there why?

[pluggy]

What cable are you using between the power supply and the Pi ?

It matters as much as the power supply itself.

[flintec]

my samsung charger cable... i dont know how much resistance it is but are there any test points on the rasp to measure the voltage?

[RaTTuS]

there are test point on the bottom of the board

[flintec]

okok gonna read the voltage and see what i get

[flintec]

4.85v so now i know why ^^ . what a huge voltage drop in such a short cable

[flintec]

just bought a 15 cm long gold plated usb cable. measuring 4.88v still getting that ****ing square... why does rasp use micro usb when the cables are ****ing garbage? its like the vi txt editor totally useless what where they thinking omg!

[pluggy]

What you got plugged into the USB ports ?. I don't think the rainbow square should show at 4.88 volts though. I was under the impression it came on about 4.65 volts.

[flintec]

seems like i have to soder my own connection or get a power supply at 5,5v to get enough voltage

[flintec]

i have a keyboard and a mouse thats all

[pluggy]

You've still got 5.17 volts at the other end ?

[flintec]

at the PSU its 5,17v on the rasp 4,88v its a really big voltage drop

[pluggy]

Does the rainbow square show all the time or just sometimes fades in and out ?

[rpdom]

I make my own cables now. Big wire works fine on lengths up to 1m/3ft. Solderable microUSB plugs are cheap on ebay. Solderable USB-A plugs aren't so cheap, so I salvage old USB plugs from broken equipment.

[flintec]

but if i remove the mouse the square doesent show up. mouse is 5v 100ma

[pluggy]

Greedy mouse (mine uses about 10mA) but it still shouldn't drop the voltage by that much. Its just a plain cabled USB mouse ?. Some wireless ones can be greedy. Do you have another mouse you could try ?

[flintec]

the square only fades in and out sometimes now like when i start the webrowser or start minecraft pi so it is better but not good enough

[flintec]

stupid square problem solved!
http://postimg.org/image/92nyctpcz/
added som hot glue to prevent stuff from moving
never micro usb again

[jamesh]

Most peculiar. Seems you have been unlucky with cables, some of them are quite bad.

The uUSB connector is well rated for the use to which the Pi puts it - insertions etc are very high, and current capacity should easily be big enough. But never underestimate the manufacturers desire to reduce costs by making the wires too thin.