READYNAS10200 hard drives don,t start up

It is unfortunate that you jumped to the conclusion that the enclosure was bad because somebody told you "the drives looked healthy".  The typical problem here is with the contents of the drives (specifically the OS partition), not a hardware failure of either the drives or the chassis. 

Continue with what StephenB is advising.  But also re-connect your old NAS to your network without drives and see if RAIDar recognizes it.  If it does, and you have a spare SATA drive (containing nothing you care about and definitely not one of your drives that were in the NAS before), see if you can create a new volume on it.  This will help determine if the chassis really is bad (which may have also caused an issue with the drive contents), or if there is something else wrong.