AutoCAD Electrical 2020 – PLC Database: Category Field Is Either Empty Or Missing Error

By Miles Nicholson

If you get the above error when creating a new parametric PLC in the PLC database, it’s because AutoCAD® Electrical is expecting key words in the Description of the device.

The category field is used to define whether the PLC is an input, output or combination / other PLC. It is an automatically populated field based on wildcard strings of the Description of the PLC. In the database an input=1, output=2 and combination=3. If one of the modules in the PLC database has a blank value, it will bring the above error message up.

There isn’t a “category” field within the Module Specifications dialogue but AutoCAD® Electrical looks at the description value of the PLC and assigns the category based on the wildcards listed below:

As an example, if you created a “24VDC Distribution Module” you would need to either add the word “*distribution*” into the wildcard strings or define the description of the PLC with “*other*” for it to be assigned a category.