We have developed a board based on PIC microcontroller which is able to generate 1kHz PWM signal to detect the vehicle and control the relay. It is also possible to adjust PWM width for current regulation. The board is ready to be installed to DIN junction box.
The EVSE KIT for DIN brings easy to install design, more functions and support of Positive and Negative PWM modulation (required by TESLA vehicles). It comes with ready-made connectors, so there is no soldering needed.
See also the EVSE section at GWL/Power blog http://gwl-power.tumblr.com/tagged/EVSE
To make your own charging station you will also need a technical skills, wires, DIN junction box and also a propper connector (Yazaki, Mennekes).
Please see manual of EVSE1.1 to see how to connect the board.
Simplified connection of 3-phase charging station