I recently bought a MAXWELL RS-150-12 switching power supply but I can't find any documentation on how to select the ac input voltage (115V or 230V).

Here is a picture of the switch: (I want to select 230V to be the input voltage)

I dont know which position sets which input voltage. My guess is: the voltage that is visible on the switch is the selected one. But I'm not sure and I dont want to damage the supply.

BTW: I only have 230V avaiable so I cannot test the setting with a lower voltage.