In 1985, the _HR_ class was split into traffic groups and relettered to separate classes.
The HZV numbers were 320 - 327, 330, 332 - 338. These were converted from HR 33, 72, 79, 84, 92, 93, 102, 111, 130, 145, 149, 150, 152, 176, 100 and 101 respectively.