Arduino + 5WG1 117-8AA12 + connect external power supply

[Dcaub]

Hello,


I have done a test to connect a arduino pro mini to a 5WG1 117-8AA12 to the knx bus and i have a working test solution with a few push buttons.

The Arduino is getting power from the 5WG1 117-8AA12 but if i want to use a bigger version of adruino the power of the BCU will not be strong enough so i want to use a external power supply to power the arduino.

I have read that it is not allowed to connect the GND from the BCU (5WG1 117-8AA12) to the GND of a external Power supply for the Arduino.

Is there anyone who have a schematic with optocouplers of a working setup ?

My electronic knowledge is a little bit far away.

Thanks


Didier

[Eugenius]

Hi,
you need ADUM1201 only between Arduino and BCU

[tuxedo]

To be more precise: Use this IC http://www.analog.com/media/en/techn...M1200_1201.pdf to do galvanic isolation between BCU and your arduino. Then you can safely power your arduino with an external power supply without interfering with KNX.

[Dcaub]

Eugenius and Tuxedo ,

Thanks for the info.

I have ordered the ADUM1201 will try next weekend i hope.

Best regards

Didier