To make it short: We did not find the right product out there, so we ended up modding one.
We bought some "Energy Saver" power strips from Zweibrueder. The devices are
very solid and not very expensive. They feature an external switch and no further intelligence.
You can place the switch in a good spot and leave the cabling under your desk.
The major drawback when using those power strips with manual on/off switches
on PCs, is that you'll have to wait for your PC to shutdown completely before pushing the off
switch. (which can take some time when running Windows ( ... installing Update 12/24 .... do not turn off ....)).
You shouldn't press the on/off-Button before complete Shutdown for obvious reasons.
To make it short: We did not like it. Nobody wanted to wait for shutdown.
The perfect power strip should:
- turn on the PC when turned on
- turn off itself completely (and all devices attached to it) after PC has shutdown
- waste NO energy while off
We came up with the idea to mod the power strip to a USB-powered power strip.
USB Ports deliver 5V as long as the PC is running. Every PC has USB-Ports and 5V are nice.
1. Push Switch on power strip
2. PCs turns on itself (BIOS Setting: restore state after power loss)
3. USB-Ports on PC supply 5V immediately
4. USB/5V powers optical relay and sustains power for PC
5. Switch on power strip can be released
6. power remains as long as the PC delivers 5V
7. After PC shutdown: 5V are missing, relay is not powered any more = everything is off
The roadmap for this mod:
- mod on/off switch to push-button
- install optical relay to override push-button during on-state
- install USB cable to power optical relay during on-state
- fit everything into switch housing
This is just how WE did it. This should only show you what is possible and leads
to a good solution.
Only try if you are aware of the high voltage running through this.
We are not responsible for anything.
elha2 - Harald Elsperger
Step 1: Parts and Details
- "Energy Saver" from Zweibrueder
- USB Cable with normal USB-Plug on one side
- some heat shrink hose
- optical relay / SSR (we used Sharp S202SE2) Datasheet
- fitting Resistor for 5V, here: 330 Ohms (see Comment below)
- Tools for cuting, welding ...
- Screwdriver (we needed to make a small cut to fit the screws, so we used a old one)
Working Point of the Solid state relay:
The typical working point is 20mA and 1.2V. (min. 8mA, max. 50 mA)
This way you'll need:
(5V - 1.2V) / 0.02 A = 190 Ohms. We choosed a 330 Ohms Resistor as it
was laying around and just draws 12 mA from the USB.
There is a note in my datasheet that the SSRs degrade over time.
This is the reason for going not to close to 8mA.
Designed for PCs
We selected parts for "normal" PC loads. You shouldn't run big loads like Motors or
Machines from the Power strip.
The Design even works well with some Satreceivers and Flat-TVs who have a USB-Port.