Let me google that for you, ha never seen that. I agree it isn't always easy to find the info. Anyway this is from the manual 4th link down in those search results:
Power Requirements : 100 - 240 V AC 50/60 Hz 60 W,
without option 35W - S6000/28W - S5000
I dare not interpret that requirement since I don't want to blow up your sampler, but it sounds like you're ok just plugging it in (?). Good to be cautious though. Maybe you can just contact Akai and ask them, they'd know! Or JD from SCSI for Samplers ..