Hello,
I searched over forum, manuals and so on, but cannot find how proper ground RB 250GS switch?
Can anyone direct me to valuable info?
Very thanks.
Best regards,
Mindaugas Rimkus
It is an indoor switch and it is not meant to be grounded. Try grounding via one of the mounting holes, if you want to use it outdoors.
Thanks for reply kirshteins, maybe You can send some picture with grounding example. My mounting hole seems to be plastic 
He means when you take the PCB out of the plastic case, obviously. There are holes with exposed GND that are perfect for grounding.