AJ Power recently designed and manufactured a 160A G10 Protection panel for use on a Solar PV system in Co Galway.

Working with Killtech Electrical Ltd, who installed the Solar PV System including Rooftop PV Panels and invertors, we completed the commissioning and witness test with an ESB Engineer at the end of November. Generators that operate in parallel with the electricity distribution system, even for a brief period, are referred to as Paralleled or Embedded Generation. Types of Generators can include Diesel, Gas, Wind and Solar PV.

Distribution network operators (DNOs) Grid Codes for both the UK (G99) and Ireland (G10) insist on an independent Protection Relay which looks at the quality and stability of the mains electricity. The relay is programmed to certain fixed parameters dictated by the DNO; these typically include under/over voltage, under/over frequency, ROCOF (rate of change of frequency) and will trip and isolate the embedded generator if the Mains Electricity is outside limits. On this project the Protection Relay utilised was a ComAp MainsPro.

The unit was programmed to ESB G10 Protection settings for Generation units <200kW. The complete G10 Panel was fully witness tested in the presence of an ESB Engineer which included Static Tests with relay injection test set (Omicron CMC156) to prove correct and accurate tripping of the Relay Dynamic Tests were also carried out to prove Primary Trip and Backup Trip devices and also a simulated loss of mains test to prove disconnect.

For further details on our special and non-standard control systems please contact us at

Back to News