Miniature Substations


Aztec’s miniature substations are undoubtedly the highest quality minisubs available on the market today. They are ideal for both mining and municipal reticulation and have proven to be perfectly suited to the harsh underground mining environment.




Aztec's minisubs are available in both air- and oil-cooled types with the air-cooled minisubs being IP rated and requiring no maintenance. The air-cooled minisubs use Vacuum Pressure Impregnated (VPI) transformers as opposed to the less rugged cast resin type.


VPI transformers are ideally suited to harsh environments and are ISO9001, SABS and IEC approved. Some further advantages of Aztec’s VPI air-cooled transformers include: the use of flame proof materials, sturdy design for high mechanical and thermal stress, no resin thus no susceptibility to cracking, IEC 76 and 85 conforming Class “C” insulation (220ºC), low losses (30% lower than cast resin), economical operation and low temperature rises and high moisture resistance.


Aztec’s minisubs range in size from the small 315kVA 6600/525V units to the larger 1000kVA 11000/550V units. Aztec’s Aztec has the capabilities to manufacture, refurbish and repair them according to the customers exact specifications.


Since quality and safety are two of Aztec’s main priorities when it comes to the manufacturing of minisubs, Aztec strives to use only the highest quality components and switchgear available. However, customers may specify particular components and switchgear as they wish provided that quality and safety are not compromised.


For detailed specifications or any queries related to Aztec’s underground miniature substations, please feel free to contact us by phone, fax or email.