NS223

NS223: Low Voltage Short Circuiting For De-Energised Work

The intent of this document is to provide a methodology to make LV mains and apparatus effectively de-energised to allow it to be worked on without using live LV working techniques. 

Scope

This standard outlines the works related to the design, manufacture and implementation of the LV
short circuits. The scope includes material that:

• Identifies the likely maximum fault capacity of the distributed energy resources.
• Outlines a specification for approved LV short circuits. This will include the minimum
  requirements for the purchase of the LV short circuits.
• Specifies the testing and maintenance required for the LV short circuits.
• Specifies the procedure for applying and removing LV short circuiting and recording
  requirements for the application and removal of the LV short circuits.

Note: The LV short circuits are required to protect against inadvertent distributed energy resources back feed or re-energisation of the LV mains only, they are not protection against re-connection to grid supply. The existing controls for grid isolation points are considered adequate.