Newmarket Junction Gets Powered


I noticed a big shed has been placed at Newmarket Junction.

Someone has painted it to ward off graffiti. Is it a workers shed, a giant portaloo, a railway- decorated Dr Who Tardis?

Not surprisingly it is to do with the pre-electrification work being done by KiwiRail.
It’s a new switching substation portacom.

There is another one at Penrose earlier this year and three more will go off Tamaki Drive, at Wiri and at Glen Eden.

A 50-tonne transformer to convert the 220kV mains grid power supply to 25kV to run the new electric trains and a backup has been installed at Penrose and another one will be at Southdown.
Newmarket’s junction is starting to look very different with the visible signs of things needed for the electric trains.




  1. Donald Neal says:

    No, it will not be to convert 220V mains to 25kV for trains. It may be to transform from 110kV transmission lines to 50kV for trains.

  2. Donald Neal says:

    Hang on, that said 220kV, not 220V. I will read more carefully. I will read more carefully. I will read more carefully.

  3. Luke says:

    the new trains do run at 25kv

  4. Ian says:

    Am I right in assuming that this 25kV is further transformed on the train to a lower voltage for the traction motors?

  5. James says:

    On the train a transformer converts te 25kV AC down to a lower voltage somewhere around 2000V AC which is then converted to DC and then to 3 phase AC at varying voltages and frequencies which is then used to drive the motors.


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