Shovel Walk Rig

Shovel Walk Rig with 2 A-trailers with generators, 1 dropdeck B trailer with HV Equipment

The shovel walk rig is 2 x 1250kVA 415V generators running synchronised in parallel to supply power to an electric shovel for fast walking around the pit.   The 415V power from the generators is stepped up to 6.6kV to run the shovel.


As the shovel advances, a truck pulls the generator arrangement along to keep it within a cable length of the shovel.

The advantages of using the shovel walk rig are:

  • No time lost to cable moves.
  • Shovel can be walking, while the cables are relocated to feed the shovel from the new location.
  • The shovel can follow a route that is not located close to powerlines as there is no need for the site substation.
  • 2x 1250kVA generators, synchronising and load sharing.
  • 1.5 MVA transformer, with earth fault current limiting Resistor, at 6.6kV. (NER)
  • High voltage switchgear with CB, earth continuity, earth fault, estops etc.
  • Customer provided short tail for HV connection.
  • All set up as minesite compliant (Intro to Site, AS3000, MDG15 compliant or risk assessed).
  • Data recording of 415V (configurable combinations of voltage, current, power, reactive power, powerfactor etc – min, max, average for 10s-1hour intervals).


  • Rig Design, Technical Information, Specification, Setup and Generator Technician – Andrew Plumridge, Genspec.
  • Transport – Keith Cox.
  • Generators – Energy Power Systems Australia (CAT Rental Power).
  • High voltage Switchgear – hired from Ampcontrol to Genspec Specification.

This rig was put together for Energy Power Systems Australia (CAT Rental Power) for a shovel walk (P&H4100, DC drive) in the Hunter Valley in Early August, 2012.