Transformer Services

WPI offer the following transformer products and services range:

■          Predictive maintenance management through oil sampling and physical inspection of transformers on site. 

A physical inspection is first carried out during the sampling process to identify leaks on the transformer.

Oil testing is carried out through an independent laboratory based in Gauteng

The following tests should be performed:

  • Dielectric Strength (KV)                      •    Moisture content (PPM)
  • Acidity (mg KOH/g)                            •    Dissolved Gas Analysis
  • Furanic Analysis Test                         •    Polychlorinated Biphenyl (PCB)

Current and historic results are compared in a spreadsheet format for trending analysis. This data should be safely stored.

■          On-site transformer repairs

This service includes, but is not limited to the repair of oil leaks, oil changes and on-site refurbishment including spray painting, re-gasketing, repairing of Buchholz relays, replacing of silica gel, upgrading of breathers, fabrication and fitment of conservator tanks, opening and inspections of transformers, replacement of burnt tap changers and replacement of auxiliary parts.

■          On or off-line purification, vacuum treatment & vacuum filling with the use of the dehydration machine

The purpose of the insulating oil is to provide insulating, cooling and performance monitoring functions. When the oil fails to provide one of these functions, oil treatment will be required to remove moisture and suspended particles from within the oil. WPI have three mobile units with the capacity to filter oil at a flow rate of 2000 litres per hour, 4000 litres per hour and 6000 litres per hour.


Oil filter