15:19 Apr 12, 2010 

It probably depends a bit on where and how this is being used?

'technology' is often marketing-ese for 'function' or 'feature' — I suspect what they may simply be getting at here is that the system has a facility for overriding the sensors — presumably so the farmer can give extra water when S/HE thinks it is needed ("Never trust these new-fangled automatic things meself!")