The downgrade package is no longer accessible on se.com, if you need to downgrade from 4.x to 3.x firmware please contact the Schneider Electric support team who will provide it to you and help with the downgrade.
The downgrade procedure is as followed :
- Step 1/ Follow Document EIO0000004992 “Installation Guide” from se.com – Chapter “FirmwareDowngradefromv4.xtov3.20/V3.30”
- Step 2/ When your CPU is downgraded to 3.20, download the firmware 3.20 ldx file available in se.com in your CPU using EADM or Unity Loader
Note: for “step 2” with EADM, you can follow chapter “FirmwareUpdateBetweenVersionsInferior/Equal tov3.x” from Document EIO0000004992 “Installation Guide”
If this procedure is not followed completely, you will encounter the following issues:
- Systematic NO CONF error appearing after an application download inside the CPU using Control Expert.
Then if the reset button of the CPS is pushed, the PLC will start with the application that have just been transferred in the CPU
- Crashes of the CPU due to a lack of ressources inside the CPU will be encountered after some hours.