The SMU 200s were QR Citytrain’s first new suburban units for 9 years since the 88-strong EMUs were introduced as part of QR’s growing electrification. Built by Walkers/Adtranz in Maryborough Queensland, the SMU 200s were of a radical new design to that of the EMUs.

They were introduced intially in 1994 for increased passenger traffic, along with offsetting loco-hauled SX Set run services that were slowly being phased out for health and safety reasons.

The units introduced modern thyristor traction control systems with configuration of the units set up similar to the EMUs of a Driver Motor Car, Motor Car and Driver Trailer Car. The SMU 200s use blowers for cooling both the traction equipment and the braking grids. Although the EMUs are louder with their high pitch traction motors, the SMU 200s (and IMU100s) are known as being quite loud on take off due to the blowers winding up. Although when running they are very quiet and have the typical gear switching sound of a thyristor control system.

Passenger comfort is provided with 2+2 seating of a mix of forward and backward facing seats, along with the usual groups of 4 facing seats. However in step with Accessbility Guidelines, they have been progressively upgraded in the last 3 years with parallel facing seating which provides room for up to 8 wheelchairs in each of the Driver Motor and Driver Trailer cars. Although seating is lost, it provides for more standing room.

The SMU200s are commonly mixed with the newer SMU220 class to make up 6-car trains, however as they use the Scharfenburg coupler they can be coupled to EMUs, IMUs, ICE sets, and Tilt Trains for haulage purposes only as they are not 100% electrically compatible.