You can raise a modification – or mod – when you want to propose a change to any part of the SQSS. 

For more information or for help raising an SQSS modification, please contact [email protected].

Search for any current or concluded modifications by name or ID. You can sort mods by ID, name, status or date of update. Or filter according to status.

Views reference
Modification status
ID Name Status Last Updated
GSR010 GSR010: Review of Onshore Entry Criteria Concluded
GSR022 GSR022: Review of Security and Economy Required Transfer Conditions Concluded
GSR020 GSR020: Modification of Clause 7.8.1.1 to Allow Single Transformer Offshore Substations of Capacity Greater Than 90MW Concluded
GSR021 GSR021: Operational and Planning Criteria for 220kV Transmission Assets Concluded
GSR018 GSR018: Treatment of Sub-Synchronous Oscillations SSO in the NETS SQSS Concluded
GSR019 GSR019: Review of Chapter 7 Double Busbar Requirements Concluded
GSR017 GSR017: Treatment of Switch Faults in Operational Timescales Concluded
GSR012 GSR012: Interconnectors Concluded
GSR013 GSR013: Review of Offshore Infeed Loss Concluded
GSR014 GSR014: Offshore Transformer Requirements Concluded

More about modifications

Modification Tracker

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Our Tracker gives you the latest details on current code modifications including the purpose and the stakeholders it affects, as well as panel comments and where it is in the review process. It is published on the 7th (or next working day) of each month.

Modification Proposal Form

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If you're thinking about raising a modification, please get in touch with us. Our experts can give you advice on your Proposal, explain how the modification process works and help to answer any questions you may have. When we receive your Proposal, we'll check it through and work together to make sure it's easy to understand.

Calendar

Once you've been in touch and are ready to write your Proposal paper, send it to us by the monthly modification submission date which you can find on our Calendar.