Mechanically Switching Capacitor (MSC)

Many of the capacitor banks installed in the early 1990s utilised a capacitor out of balance protection relay produced by GEC, Type DTCB 11.

Leaving the existing relays in service may result in their failure, as a number have done already, this is a potential risk. This would leave the equipment unprotected and out of service. Therefore, a modern replacement protection relay was required to give reliable operational capacity.

Morson Projects were awarded the project by National Grid to upgrade the out of balance protection on MSCs at a number of substations in the Midlands and the South.

To upgrade the current MSC protection, Morson Projects responsibilities were to carry out site surveys to identify the extent of any new design or installation works.

Morson Projects were to supply a fully compliant type registered solution to UKBP/TP 183, complete with design and setting design assurance carried out in house.

Once these stages were met, 20 protection schemes were designed and manufactured in house by Morson Projects in our workshop; these then underwent a full National Grid Factory Acceptance Test (FAT) by the client prior to leaving for site.

All interface design works and design assurance were carried out by our dedicated Power Engineering Team. Our Installation & Commissioning department supplied all installation and commissioning required, supported by their own TP144 Site Management and TP141 Commissioning Team.