Overview of power switch options for the Raspberry Pi [day 13 of 20-days-of-posts series]

A power switch was omitted in the design of the Raspberry Pi to keep costs down.  There was no easy interface provided to add one either, but there are many different options.  I had previously tackled the original topic in a previous post, comparing a few options, including building your circuit.

Challenge:  The Raspberry Pi always remains powered-on as long as there is power coming in on the micro-USB power line.  A shutdown/halt/poweroff command will shutdown the OS and leave the system in a powered on but idle state.  The power consumption would be unchanged between idle and active on the Raspberry Pi.  Further, to turn the system back on, the USB cable needs to be unplugged or the power supply needs to be unplugged (reset).

Ideally we need....

• something that powers the raspberry pi off when it is shutdown (power consumption becomes negligible / < 0.5 W) [POWER OFF]
• something that can trigger a clean software shutdown [CLEAN SHUTDOWN]

Over the past few months since the  original topic / post, I've covered the following options:

1. make your own circuit,
2. repurpose a USB Big Red Button,
3. illuminated and rocker-style power switches by Mausberry Circuits
4. WeMo [Insight] Switch by Belkin
5. RemotePi Board by MSL Digital Solutions

I've felt it was time to do a head-to-head comparison of the five options that were discussed in the previous posts.

Assumptions:

• all values are in USD; shipping costs and taxes are excluded throughout 
• measurements are based on a scale of 1 - 5

	Build Your Own Circuit	USB Big Red Button	illuminated / rocker-style by Mausberry Circuits	WeMo Switch by Belkin	RemotePi Board by MSL Digital Solutions
Product Page	n/a	link	illuminated switch rocker switch generic USB switch custom switch	WeMo	RemotePI
Price	varies based on parts ($ 5 - $ 40)	$ 1 - $ 7	$ 14 - $ 16	$ 50	$ 24 - $ 27
Integration	bulky setup	plug into free USB port	3 jumper wires hooked upto GPIO	plug Pi USB power plug into	locks onto GPIO
Easy of Hardware Setup	1 / 5 - soldering required	5 / 5 - plug-and-play - solder-free	4 / 5 - risk of causing damage if you place the cables on the wrong pins - solder-free	5 / 5 plugs in	5 / 5 - plugs in, screws on - solder-free
Easy of Software Setup	1 / 5 - requires writing your own app	2 / 5 requires installing apt-get packages, compiling and provided C code	4 / 5 - run switch.sh install - default script had issue causing crashing Pi, some modification needed to code	2 / 5 - requires phone app - firmware and app buggy	4 / 5 - run irswitch.sh install - program power button on remote - setup lird.conf for remote
Reset Button [hard reset]?	DEPENDS if intercepts power source	NO	iluminated switch NO rocker switch YES	NO	NO
Safe Shutdown?	YES	YES	YES	NO (use some thought process around shutdowns)	YES
Power Consumption [as measured by a kill-a-watt]	negligible	negligible	negligible	1.5 - 2.5 W just as much power as the Pi!	negligible
Completely Powers off Pi?	DEPENDS if intercepts power source	NO	YES	YES	YES
Powers Pi by	GPIO, micro USB or USB (Pi rev B)	n/a	micro USB via micro USB	micro USB or USB port (Pi rev B)	GPIO via micro USB
Shutdown Scripts		device driver	RaspBMC/Raspbian/Debian OpenELEC Arch	n/a	OpenElec RaspBMC XBian
Major Selling Features	- switches can be used for other purposes	- switches can be used for other purposes	- select models include reset switch - rocker switch (left in on position) works with well WeMo to power on remotely	- power on Pi using different conditions - remote power on / off / reboot	- includes IR receiver for XBMC - only solution that can power on Pi via IR
Full Review	previous post	previous post	previous post	previous post	previous post
My Sample Integration	n/a	n/a	rocker switch illuminated switch	n/a	RemotePi