Dangers of Overloading Transformers

Transformers play a crucial role in delivering electricity safely to our homes and businesses, but overloading them with illegal connections, can lead to serious consequences.

Transformers don’t blow because of poor maintenance.
The voltage on the lines coming into residential areas is too high for consumption in homes.  The transformers (mostly green boxes on street poles) lower the voltage from 22 000 volt /11 000 volt on the network to the 400V/230V that can be used in homes. 

  • Overloading: Transformers are designed to supply electricity to a specific load, not necessarily the number of homes.  If people connect illegally on a network, this overloads the transformer, and they then blow because they are designed for a specific load.  Eskom or the municipality must then first remove the illegal connections before replacing or repairing the transformer, otherwise it will blow up again.
  • Tampering:  People either try to connect illegally to the transformers or they drain oil from the transformers.  Both activities will destroy the transformers.
  • Maintenance: Only inspections are done on the condition of the transformer and the associated equipment.  Most breakdowns of transformers are due to overloading and tampering.

It costs no less than R60 000 to replace a transformer in a residential area, besides the labour costs and the revenue loss.  Importantly, there is the inconvenience caused by power outages to the customers.