Hi,
Removing the plecs blocks may introduce various errors in your model. It is better to install the blockset instead. You can download the latest PLECS blockset from their official source: PLECS Blockset Packages | Plexim. Once downlaoded follow these instructions for installation: Installing PLECS Blockset | Plexim.
For more information on how to use this blockset with Simulink follow these resources:
- https://www.plexim.com/support/videos/introduction-plecs-blockset
- https://www.plexim.com/sites/default/files/plecsmanual.pdf
Hope this helps!