By David Wren
When using the ‘18th Edition to Amendment 2’ version of Wiring to open up a CYW project from a previous version of the program, due to the number of updates and regulatory changes that have been made to the program, there will be the pop-up message box below:
This message box is advising you to continue to open the file in the latest version of the program to ensure it meets the new requirements of BS 7671:2018 Amendment 2:2022.
Once the update is applied, it is fixed and there is no going back. For this reason if you are unsure about upgrading your project, it is advisable to first make a copy of the Wiring project, by performing a ‘Save As’ and give it a versioned project title. E.g. in your previous version of the Wiring program, create a copy (Save As) to make a new version of ‘Milford.CYW’ as ‘Milford_A2.CYW’.
Now you can open the new ‘A2’ version of the project and opt for ‘Yes’ to fire it up in the 18th Ed Amd 2 version of the program. Then you can review any varying calculation results and regulation changes, such as AFDD or SPD requirements etc and decide if you want to permanently update your project to the later standards.