When it comes to naming drawings, wires, and devices in an electrical drawing package, it is extremely important to stick to a standardized numbering structure across all projects. The benefits of doing so are endless. Including the necessary components of a schematic naming convention can provide the following benefits:
Drawings. The first thing a naming convention needs is a way to name each drawing in the package. At Fusion, we reserve certain page numbers for different types of circuits. For example, all of a panel’s main AC power distributions drawings are numbered from 100 through 109. Although most panels only need one or two AC power distributions drawings, we reserve 10 pages to ensure that we do not have to “overlap” the next reserved section if we ever have a larger number of AC power distribution drawings. This would muddle our typical naming convention. It is important to be specific when defining the reserved page number categories, so that you don’t have to redefine new reserved page numbers every time something out of the ordinary comes up. As a contract manufacturer, we reserve a specific range of drawing numbers for an index drawing, a symbol drawing, a general specification drawing, a system layout drawing, AC distribution, VFD motors, servo motors, 24 DC power distribution, safety circuit wiring, machine interlocks, PLC layout and I/O card wiring, main enclosure layouts, control station layouts, junction box layouts, terminal block detail drawings, plug detail drawings, cable detail drawings, and other device detail drawings as needed. Having these categories defined, and adhering to the numbering convention allows us to save time and money by reusing generic templates for each drawing type.
Wires and Components. The next thing a naming convention needs is a way to name wires and components. At Fusion, we name wires based on the drawing and line number from where they originate. If multiple wires originate on the same line, we append the letter “A” to the wire label, and we continue through the alphabet for each additional wire that originates on that line. For example, if three wires originate on drawing 220, line 10, the wires get labels (from left to right) “220-10,” “220-10A,” and “220-10B.” This way, a technician in the field who is troubleshooting the panel can grab any wire, look at the label, and be able to easily find where that wire originates in the drawing package. Components also are labeled based on their location in the schematics, as well as a two or three-character description of what the component is. For example, a fuse that is drawn on page 100, line 20, gets the label “100FU20.” When a device has pins that are drawn on different pages (such as a control relay, which might have its coil pins drawn on one page, and different contact pins drawn on others) the device gets its label based on where the power to that device is shown. For example, if a control relay’s coil is drawn on page 300, line 02, it gets the label “300CR02,” and this label is used throughout the drawing package to identify the contacts that belong to this coil, which might not be drawn on the same page. Just like with wire labels, the technician can look at any component in the panel, and be able to find it in the schematics with ease. The picture below shows an example of the typical component and wiring convention used at Fusion.
Implementing a standardized naming convention for your electrical schematics is a necessity, and there are many benefits that come along with doing so. Giving different drawing categories a reserved range of drawing numbers creates familiarity across different drawing packages, and allows the engineer to save time when creating a new drawing package by using generic templates for each drawing type. Naming wires and components based on their drawing and line number of origin helps field technicians easily troubleshoot any issues because they will be able to use component and wire numbers to easily find the information they need from the schematics. This is just one of many lean practices that our Engineering team uses to produce quality work consistently.