As of October 2003, OSRAM has improved the HSD 575/72 lamp by lowering the start voltage to 1.5 kV. This solves the compatibility problems with magnetic ballast fixtures that we wrote about in May. See

Improved lamps have the following or higher batch codes:

  • C3a8
  • C3b8
  • C3c8

The HSD 575/72 provides an average service life of 3000 hours and and a color temperature of 7200K. We approve the improved version of lamp for use in the following fixtures.

  • Exterior 600
  • Exterior 600 Compact
  • MAC 500
  • MAC 600
  • MAC 600 NT
  • RoboScan Pro 918