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Building Intelligent Symbol Libraries

More and more utilities and engineering firms are making the switch to AutoCAD Electrical and the SDS Toolkit for P&C substation design. It’s an exciting time for our industry, and while it’s not my place to name names, there are major organizations leading the way toward industry-wide intelligent substation design. But what does it take to make this kind of transition? One of the biggest hurdles in making the transition to AutoCAD Electrical and the SDS Toolkit is the development of intelligent symbol libraries. AutoCAD Electrical utilizes a blocks+attributes approach, which is what gives it so much of its power and intelligence. And that’s all that an AutoCAD Electrical symbol is: a block with attributes. That may not sound like such a big deal, but a quick scan through a substation drawing set will remind you just how many different symbols you use on a given project, and just how daunting a task it can be to create intelligent symbol libraries. Some intelligent symbol libraries that I’ve helped to develop in the past have over 800 unique symbols! If you count on an average of 15 minutes to create each symbol (many take less, but there are some that take much, much more), you’re looking at spending up to 200 hours on symbol creation — and that’s if you know what you’re doing! Here are some things to consider as you build your custom, intelligent symbol libraries. Organization AutoCAD Electrical looks for two unique symbol libraries: the schematic library and the panel library. At the very least, you’ll need to have all of your schematic symbols stored in the schematic library, and all of your panel symbols (including both front and rear view) in the panel library. It’s important to keep these two basic types of symbols separated. However, if you have 800 symbols or more in your libraries, scanning through all of those files can be a frustrating and time-consuming experience. Several of my clients have decided to break each primary folder down into subfolders organized by families. So all of the schematic protective relays go in one subfolder, all of the fuses in another, and all of the terminals in yet another — you get the idea. The biggest benefit to this approach is that you know exactly where to go to find what you’re looking for. However, you’ll also have to be sure to add each and…

Holt Design Tools for Designing Symbols

I’m pleased to offer a great set of tools for AutoCAD Electrical symbol building – for free! These tools are designed with substation designers in mind, allowing them to create large-scale symbols (think SEL relay wiring diagram symbols) with ease and efficiency. Here’s a brief glimpse of what’s included. IAN – This tool allows users to automatically increment attribute names, so that TERM01 becomes TERM02 with just a single click! IAV – Similar to IAN, except that instead of incrementing attribute names, this tool increments attribute values. CHA_DIR – This tool lets users quickly and painlessly change the direction of attributes like X1TERM01. That means you can change X1TERM01 to X4TERM01 with just a click! REORDER_ATTDEF – In the Enhanced Attribute Editor inside of AutoCAD Electrical, attributes appear in the order in which they were placed on the symbol drawing. But with this tool, attributes are reordered so that they appear in a logical and functional order. AGAP – This tool creates a user-defined gap between attributes, making symbols look clean and professional. Full documentation is included with the download. Just click on the link to download the .zip file, and then extract it in a convenient location on your local drive. Open any AutoCAD Electrical drawing, and the file holtdesign.fas to the Startup Suite by using the command APPLOAD. Now the file will automatically load with every new drawing you open. We’re confident that you’re going to love these tools, and that they will make symbol building so much more fun and efficient! Note (11-28-18): The design tools have been updated to correct an issue with the AGAP tool requiring the user to be running the SDS toolkit in AutoCAD Electrical.

Connect Wires with Different Wire Numbers to the Same Terminal

One common situation in substation designs is connecting multiple wires with different wire numbers to the same terminal. The design calls for the wire number to break as it passes through the terminal point, even though the drawing might not show all of this information. AutoCAD® Electrical allows you to connect multiple wires with different wire numbers to the same terminal. The trick is using the correct terminal symbol. It’s important to know how AutoCAD® Electrical handles schematic symbol block names. You can read all the details about schematic symbols here, but when it comes to terminal symbols, this is what you need to know. The first two characters in the file name must be either HT (for horizontal terminals) or VT (for vertical terminals). The third character is the one that determines what kind of terminal it is. To create a terminal that does not break the wire number, use a ‘0’ in that third position. But if you need a terminal that does break the wire number, the third character should be a ‘1’. So a square terminal block that breaks the wire number might have a name of HT10_SQUARE.dwg, VT1001_SQ.dwg, or whatever fits your needs. This seems like basic information, but if you don’t know about the schematic symbol naming convention, you won’t know how to wire up these terminals. Before I had this information, I spent a couple very frustrating hours naming and renaming wires, only to have my entire wire network get all screwed up! The simplest solution, of course, was to swap an HT1* symbol in for the HT0* symbol that was already on the drawing. This little tip has been a game changer in my design philosophy. One of my clients only wants “external” wires to have wire numbers. This means that every wire that changes LOC (location) code from one end to the other needs to be numbered. When this is drafted, however, the wire most likely runs from something like a protection relay in location 1, passes through two terminals (one in location 1 and the other in location 2), and ends up in something like a control relay in location 2. When drawn, this looks like a single wire segment with two terminals on it. However, if the two terminals are wire-breaking terminals, the segment between them can be assigned a wire number, and the two segments on either side will remain…