Can I connect a SUN2000-30/36/40KTL-M3, 60KTL-M0 or 100KTL-M1 to the internet without Smartlogger3000, only with a SmartDongle?

Yes.

This is possible with a SmartDongle. However, with the 60KTL-M0 and the 100KTL-M1, only the SmartDongle 4G is compatible.