fault on my samsung sps1000 till?

Classic symptoms of scrambled memory, so they will need to be re-programmed.
Leave them turned on for 24hrs to charge up, then perform the memory clear and run through the various setup tables in the manual.

If you don't have a manual, c-tech has the full SPS-1000 programming manual here:

http://the-checkout-tech.com/manuals/TOC/cashregisters/Samsung/SPS-1000%20programming.TOC.pdf

Also, the operation manual is here:

http://the-checkout-tech.com/manuals/cashregisters/Samsung_SPS-1000_operating_manual.html

Registerman
February 2011