The Variotram prompts a lot of questions, particularly the technological leap between the Sydney R1 class tram and the Variotram, and the fact our museum tramway is built to ‘traditional’ tramway standards.
Current status as of June 2025
Variotram 2107 is operable, but not yet certified for passenger operations and so remains in ‘display condition’. However the tram is stored out of public view in the secondary operations building, meaning that it is not suitable for members of the public to view except on special events, when the tram is out on display.
Thanks to Transport Heritage NSW, the wheel flanges and heavy rail step backs have been re-profiled to enable the tram to pass through museum’s ‘traditional’ Sydney tramway points. The air-conditioning has also been overhauled and the saloon lights replaced with 24v LED tubes. (Many of the original fluorescent inverters had burned out). Works planned in the near future include continued replacement of expired electronic components, roof resealing and a swap of air-conditioning units with fully overhauled spares.
The museum overhead is not yet pantograph ready; various overhead frogs around Cross Street and the scissors crossover need to be properly adjusted for pantograph operation. There are also several locations along the museum’s running lines where overhead fittings still need to be swapped out for pantograph friendly types, or have adjustments made.
Can 2107 operate on 600V?
The tram can operate (at reduced power) down to 500V. No modification was needed; that is the ‘way it came’. The main issue has been the regenerative braking which would raise the overhead voltage to approximately 900 volts; way too high for our heritage fleet that might be running at the same time. In June 2020, new software was installed and braking tests conducted which verified that the voltage was now maxing out at 735v. While still high, this has been deemed an acceptable limit.
If the overhead line is detected as not being ‘receptive’ to regenerative braking, the tram will automatically switch to on board dynamic braking resistors. These resistors are sized to enable the full emergency braking load to be absorbed.
The Mannheim (Germany) Variotrams could change from -750V supply to +600V supply and back without stopping. (Mannheim was -750V and Heidelberg was +600V, the trams through run between the two cities). This adaptive ability is a key part of the ‘Drive Control Unit’ software.
Can your substation power such a large tram?
The peak power draw for 2107 (including air-conditioning) is less than that for PCC 1014. However, tests at the end of the National Park line will be required to confirm calculations on voltage drop. 1014 will still move when the voltage drops below 500V; 2107 will not.
The traction converter pods on 2107 are rated at 166 amps input each. This the maximum rating – not a typical rating. The Auxiliary converter is rated at approximately 100 amps DC input, again this is a maximum, not typical.
This gives approximately 440 amps maximum draw. A typical traditional bogie tram has it’s line breaker set to 300 amps.
Are you going to fit trolley poles to 2107?
No. Such a modification would be out of character for the vehicle.
Who owns 2107?
2107 is part of the State Movable Heritage Collection and as such is owned by Transport Asset Manager of NSW and ‘managed’ by Transport Heritage NSW. The Sydney Tram Museum are the ‘custodians’ of the asset on their behalf.
