With the construction of the new line from Launceston to Bell Bay, the Tasmanian Government Railways placed an order for four 1752 kW locomotives with English Electric. However, with the locomotive still under development, it was decided to purchase four 1380 kW locomotives that were an evolution of the Western Australian RA class locomotives with a low nose profile and vacuum brakes.[1][2] At 96 tons, they were considerably heavier than the previous heaviest locomotives on the network, the Y class at 58 tons, requiring significant upgrades to infrastructure.[3] The first was delivered in December 1972.[4][5]
In March 1978 the Z class were included in the transfer of the Tasmanian Government Railways to Australian National. In 1984/85 all had their vacuum brakes replaced with air brakes.[6][7]
In June 1998, they were renumbered as the 2110 class.[8] All four locomotives were modified for driver-only operation between 1998 and 2001, by having their noses lowered further and the size of the front cab windows increased.
All remained in service with TasRail until stored in May 2014 with the entry into service of the new TR class.
In 2022, The Q Train acquired Z1 and Z4 for revenue use on their restaurant rail services on the Bellarine Railway. Z1 was delivered in March and Z4 in May.[9] Z2 and Z3 were donated to the Don River Railway. Z4 entered service in February 2024, with Z1 following in June 2025. It is common to see the Bellarine locomotives running long end leading, something which was never done in Tasmania. As of 2025 and onwards, all 4 members of the class have survived into preservation.