Annex 1 and Annex 2 Documents

Standards and other documents referenced in Annex 1 and Annex 2 of the Distribution Code are available for free and can be downloaded below:

Annex 1 Documents

1. Engineering Recommendation G5/4-1

Planning levels for harmonic voltage distortion and the connection of non-linear equipment to transmission and distribution systems in the United Kingdom

2. Engineering Recommendation G12/4-1

Requirements for the application of protective multiple earthing to low voltage networks

3. Engineering Recommendation G59/3-2

Recommendation for the connection of generating plant to the distribution systems of licensed distribution network operators

Please note: Engineering Recommendation G59/3-3 will come into effect from 1 February 2018 and will replace Engineering Recommendation G59/3-2

Click here to download a copy of Engineering Recommendation G59/3-3

4(a). Engineering Recommendation P2/6

Security of Supply

4(b). P0-PS-037 (EM7907)

Distribution planning standards of voltage and of security of supply. (Parts of Scottish Hydro Electric Power Distribution Ltd Area)

5. Engineering Recommendation P14

Preferred switchgear ratings

6. Engineering Recommendation P24

AC traction supplies to British Rail

7. Engineering Recommendation P25

The short circuit characteristics of electricity boards low voltage distribution networks and the co-ordination of overcurrent protective devices on 230V single phase supplies up to 100A

8. Engineering Recommendation P26/1

The estimation of the maximum prospective short circuit current for three phase 415V supplies

9. Engineering Recommendation P28

Planning limits for voltage fluctuations caused by industrial, commercial and domestic equipment in the United Kingdom

10. Engineering Recommendation P29

Planning limits for voltage unbalance in the United Kingdom for 132kV and below

11. Technical Specification 41-24 November 2009

Guidance for the design, installation, testing and maintenance of main earthing systems in substations

12. Engineering Recommendation S34

A guide for assessing the rise of earth potential at substation sites

13. Engineering Recommendation G83/2

Recommendations For The Connection of Type Tested Small-Scale Embedded Generators (Up To 16 A Per Phase) In Parallel With Public Low-Voltage Distribution Networks

Annex 2 Documents