In electrical design, how we choose to represent connections between electrical devices in our schematics is often open to interpretation. If we’re not careful, our design intent can be easily miscommunicated to the reader, leading to potentially disastrous results. “The danger is in the details,” as they say. SOLIDWORKS Electrical provides some powerful methods of ensuring that nothing is lost in translation, but many designers frequently overlook them. Today’s blog will focus on how you can avoid costly and time-consuming errors in testing and assembly, by spending just a bit more time clarifying your schematic connections. Let’s begin.
Contactor Holding Circuit
Let’s take a look at a pretty simple connection that can still be easily misinterpreted if we’re not careful – a contactor holding circuit. This type of circuit is employed when we want a contactor (CR1) to stay engaged after a momentary contact pushbutton (PB4) is pressed by a technician. The pushbutton in this scenario is also illuminated. While the system is engaged, we’d like the light to stay and remain on until S1 breaks the circuit. The connection pictured is between two devices and is facilitated by three wires.
As an electrical designer handed these requirements, the way this should be wired is perhaps obvious. However, to an untrained technician or layperson, the chances that at least one head-scratch will occur is quite high. When you have more than one wire represented on a given potential, this is called a “complex equipotential” in the software. Complex equipotentials need to be defined and clarified so that miswiring does not occur when interpreting the schematics or downstream publications, such as wire run lists. In SOLIDWORKS Electrical, this is done using a tool called Wire Cabling Order. It can be accessed by right-clicking on any member of the complex equipotential and selecting “Wire cabling order."
Wire Cabling Order
The Wire Cabling Order command is more intimidating than most aspects of the program, so it’s worth breaking it down into 3 distinct sections:
- Equipotentials - The project level version of this command (Project>Wire Cabling Order) allows you to see every complex potential in the project, and this section of the menu allows a user to set the focus of the tool on a particular equipotential. However, it’s usually more practical to do this on the front end by right-clicking the potential of interest to launch the command.
This panel also reflects the status of the equipotential – the field for “Wire” and “Cables” will be marked as “Incomplete” if the number of wires or connections made in the dialog does not match what has been drawn on the schematic.
- Components - This section is a list of all components and connection points on the selected equipotential. When selecting a connected device, a preview window will display the symbol which was used to represent the device for context.
- Wires - This section describes all the wires which are used to facilitate connections between connected components on the selected equipotential. Each wire is represented by a row.
The primary function of Wire Cabling Order is to set the Origin and Destination field for each wire to be consistent with the design intent of the project requirements. This can be achieved by:
- Select one or more wires whose origin or destination needs to be modified
- Select the component connection point that you’d like to replace the connection with
- Select the button at the bottom of the components panel corresponding with the intended change
- Replace origin with point
- Replace destination with point
You may also drag and drop the connection point from the components panel to the origin or destination field in the wires panel.
By explicitly stating how you’d like each wire in the potential to connect to each component, you ensure the wire run lists that are automatically published to Excel, accurately reflect your expectations for the system. What’s more: if you have the SOLIDWORKS Electrical 3D add-in for SOLIDWORKS, you ensure the wires automatically routed in your mechanical assemblies are also following the plan.
One final option to consider, is to trade out connection dots for nodal indicators. Nodal indicators are small branches that are automatically placed at wire intersections to indicate the underlying cabling order. The option to enable nodal indicators can be found in your project configuration settings under the Graphics tab. This small change can really punch up the clarity of your schematics and reduce misinterpretations of your designs. Give them a try!
Want to know more about how to stay organized with your cabling? Learn how SOLIDWORKS Electrical can help you manage schematic designs by drawing wires with a selected wire style to create a cleaner, more organized schematic design.