Posts: 103
Joined: Mon Oct 01, 2012 6:55 pm

Help testing power

Sat Oct 27, 2012 9:44 pm

So I have not had much luck with my Pi so far. I have been trying to run RaspBMC on it and keeps hanging/crashing and giving error messages. I have found a bad network cable (and made a new one and tested as good), had a bad card reader (now have a good one), and the new SD card that I bought (Adata class 10 8gb - listed as working) just keeps throwing errors after continuous use.
So I have a new SD card on order and am wondering what else could be wrong.

Today I tested the 2 power to usb adapters (one is a genuine apple 5v 1a output) the other is the same, but is a dve switching adapter (no clue what that is from). When I plugged in my Blackberry to them to charge it said insufficient power, so now I am thinking my chargers are not good. I have measured the voltage across the TP1 and TP2 pins with both chargers and am getting 5v with no noticable drops.

Is there any way to test the chargers and see if they are outputting the correct voltage and amperage?
I also have a LG adapter for my phone listed as 5.1v 700ma and that will charge my BB fine and tested the same on my RPi.

Please help me sort this out!

p.s. I have this hub on order ... 00_s00_i00 that will be here in a couple days and hopefully that will power the RPi ok.

ITz Life NL
Posts: 27
Joined: Fri Jul 20, 2012 5:02 pm

Re: Help testing power

Sun Oct 28, 2012 11:05 pm

do you have a keyboard plugged in ? if so unplug it this kept happening to me aswell

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Re: Help testing power

Mon Oct 29, 2012 12:06 am

If you see a stable 5V between TP1 and TP2 I would assume that the PSU is indeed able to support the current the PI needs. If it wouldn't the voltage would drop.

Which PI do you have, a model 1, or the model 2 with mounting holes?
If its a model 1, do you have polyfuses at F1 and F2, or black things with a zero printed on them?

generally simple keyboards should work fine, its only the fancy ones that can generate problems.
but when testing its always sensible to remove as much as is possible, then if everything works add things back one at a time, to see of the problem returns.

Posts: 103
Joined: Mon Oct 01, 2012 6:55 pm

Re: Help testing power

Mon Oct 29, 2012 4:36 am

I have the 512mb version. Normally I have my Logitech MK3200 plugged in, but I experience hangs and crashes with using just my HDMI CEC remote.

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