Power Monitor Raspberry Pi B+, Pi 2, and Orange Pi PC

I ordered up a USB power monitor. I wanted to see what my power usage was. So here is what I got from the following Pi’s.

Tested the following.

Raspberry Pi B+
Raspberry Pi 2
Orange Pi PC

Interesting, less than i expected for the OPI. What do you see with a dongle plugged in?

This is with the USB dongle plugged in that I am using for FlightAware. All 3 has USB dongles plugged in and all 3 are on a LAN connection. During the test.

Ok thanks, Sounds like the recommended 1.5A supply is way overkill.

No, not at all. Don’t fall into that. Skimping on the power supply will cause random crashes and errors.

Good info. Thanks for sharing.

So did you try to get Wifi working on the OPi?

I am also interested to know the answer of jepolch’s question, from you or any one who has an Orange PI PC.

I remember your wifi dongle does not work with opi pc / debian_jessie_mini. I dont have a wifi dongle to give a try.
I read somewhere in OPi forums (cant find the page now) that this wifi dongle worked for the writer of that post:

Mini USB 150M 150Mbps Wireless LAN Adapter 802.11b/n/g WiFi w/ 2dBi Antenna UL

$2.97+ free shipping from Hong Kong :slight_smile:.
I will order one, for $3 it is worth trying… success or dongle >> trash can

Not really - the maximum rated output of a power supply doesn’t tell the whole story. You don’t know how that power supply behaves under load and it is often the case, especially with cheaper items, that they don’t maintain the 5v supply properly as the load increases. A well designed power supply will be capable of giving the rated voltage, and the maximum rated current without becoming unstable or the voltage dropping.

The quality of output is equally as important as the ability to deliver the rated power. I’d suggest having a read of this page: lygte-info.dk/info/usbPowerS … %20UK.html

Here is the difference between a cheap crappy supply and a decent one:

This one shows a ripple of 0.4v when under a 0.5A load and a lot of noise. Running a computer off this would not give good results:

Conversely, here is a decent supply loaded to 2A. There is barely any ripple and low noise:

Differences like this are why people can have problems with stability, even when they are using a power supply that on the face of it should be OK.

I tried one of those previously, but it never worked properly whether I connected it to a raspberry pi or to a PC. It wouldn’t maintain a connection to the network. I got a refund for it, but at that price it’s worth a go.

I am running the Orange Pi on a LAN connection. But maybe I’ll try a wifi adapter just to see.

I’m not using a standard power supply for my Pi’s. I am using a 12 Volt to 5 Volt converter that has USB’s on it.

I use the 12V to 5v for this reason.

I picked up the WiFi adapter for AP monitor mode for Kali Linux, but I added up using it for my one Flight Aware site. It’s been running for months with no issues at all so far.

amazon.com/dp/B002GBPE34/re … Gwb87VFG33

You can also reduce power by turning off the HDMI port. If you are running the Pi headless. I seen this online and is what it says.

This tip has been suggested by many people. If your system is headless (no video output) you can turn off the HDMI port with:
sudo /opt/vc/bin/tvservice -o
to turn it back on:
sudo /opt/vc/bin/tvservice -p
This command will save you around 20-30mA.

More good info. Thanks! I’ll do this right now. (Of course, I will soon forget I did this and wonder why the HDMI doesn’t output to the TV :laughing: No, I’m putting it in my notes.)

No problem. :smiley:

With the Orange Pi issue with USB wireless cards. I wonder if it’s because of this not being installed?

sudo apt-get install firmware-linux-nonfree wireless-tools wpasupplicant -y

It’s just a guess. :open_mouth:

Thanks caius, good point.
If i have the OPI board in the house it runs on a 1 amp samsung phone charger Ok, but i assume its reasonable quality, otherwise when its at home in the roof it runs on a ~4A 12v to 5v converter.
Both appear to run it ok but I with check with a scope one day, probably will be horrified by what i see. :laughing: