You give little detail.
It's a mixer
Probably 230 V
Probably 4 wires
Probably 4 terminals on the switch
Probably two buttons - Green for On and Red for Off - a safety switch that needs to be reset if the power drops out.
But you do not say...
If it's like I suggest it might be - rig up two wires to the mains and connect them to any two terminals and press the green button. If the switch latches than those two terminals are the input and the other two terminals the output.
If nothing happens when you press the green button then adjust the connections and keep trying until you get it right.
You can do this on a bench or in your kitchen - you will not damage the switch. Just don't electrocute yourself.
If the switch is not as I surmise then all bets are off.
I can't find it in my heart to wish you luck..., January 2015