Zuki,
Nearly all sustain pedals are normally open leaf switches. Most keyboards, however, have an option where you can select the type you have and it will default to the selection upon start-up. I don't recommend cutting wires, mainly because there's a 66 percent chance of cutting the wrong wire.
Gary
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PSR-S950, TC Helicon Harmony-M, Digitech VR, Samson Q7, Sennheiser E855, Custom Console, and lots of other silly stuff!
K+E=W (Knowledge Plus Experience = Wisdom.)