The One-Line Diagram Distribution Equipment Blocks commands allow you to customize the list of blocks available to be used for distribution equipment on the one-line diagram.
See the Block Creation section for more information about creating new blocks.
See the General Customization Commands section for more information about how the Edit Project List, Edit Master List, Copy Project List to Master, and Copy Master List to Project commands work.
To edit the one-line diagram distribution equipment blocks project list, go to
Ribbon: DME: Customization->Project Customization-> 
One-Line Diagram Distribution Equipment Blocks
Pulldown Menu: DM Electrical->Customization->One-Line Diagram Distribution Equipment Blocks->Edit Project List
To edit the one-line diagram distribution equipment blocks master list, go to
Ribbon: DME: Customization->Master & Standards Customization-> 
One-Line Diagram Distribution Equipment Blocks
Pulldown Menu: DM Electrical->Customization->One-Line Diagram Distribution Equipment Blocks->Edit Master List
One-line Diagram Distribution Equipment Blocks Dialog Box
Sort: Press this button to sort the list of blocks alphabetically by the Description column.
Move Up: Press this button to move the selected block up in the list of blocks.
Move Down: Press this button to move the selected block down in the list of blocks.
New: Press this button to create a new block.
Delete: Press this button to delete the selected block. If the block is currently used by a record in the schedule, you will be asked if you want to replace the block in the schedule with another block.
See the Common Block Information section for more information about the Description and Block Name values that can be specified for one-line diagram distribution equipment blocks.