Below-Grade Automation in SDS-Physical

Faster, More Accurate Substation Design

Designing below-grade systems is one of the most detail-heavy and risk-sensitive aspects of substation engineering. Cable trenches, conduits, control circuits, grounding grids, and routing paths all need to be placed accurately in three dimensions and kept consistent as the design evolves. Small errors underground can lead to costly rework, construction delays, and safety hazards.

To streamline this process, many utilities and engineering firms rely on Substation Design Suite – Physical, a purpose-built design environment for substation physical layouts. One of its biggest strengths, and one of the areas where we consistently hear from designers about major time savings, is its automation for below-grade infrastructure.

In this post and the video below, we’ll walk through what makes the SDS-Physical for AutoCAD below-grade tools so powerful and why these capabilities have become meaningful differentiators for substation design teams.

A Unified Way to Model Below-Grade Infrastructure

Below-grade work is inherently multi-layered. Designers need to manage conduit systems, power and control cables, junction boxes, trench routes, grounding grids, equipment connections, and depth, spacing, and clearance rules.

SDS-Physical brings all of these elements into a single environment with configurable feature types, rule-driven validation, and dynamic updates. Designers can build or modify trench routes, place multi-row conduit banks, and assign cable types quickly using intuitive ribbon tools inside AutoCAD.

Because SDS-Physical treats these items as intelligent objects rather than simple lines, designers get immediate improvements in accuracy, consistency, and maintainability across the design.

Automatic Handling of Segments, Conductors, and Contained Features

One of the recurring challenges in below-grade design is maintaining accurate, consistent conductor behavior across structures and equipment. In SDS-Physical:

• Conductors run continuously across the design unless broken by a device.
• Segments run structure-to-structure.
• Contained features allow conduits, power cables, and communication lines to be organized within a single trench or conduit feature.

This model reflects the way substations are actually built and eliminates manual tracking. Adding a new cable to an existing conduit, for example, is simply a matter of selecting the container and choosing the conductor type. SDS-Physical then validates spacing and conduit size automatically.

Designers frequently cite this one-click modification workflow as a major source of time savings.

Dynamic Conduit and Trench Routing Tools

SDS-Physical includes tools for routing conduits and trenches that dramatically reduce the time spent on manual geometry updates. Designers can define:

• Depth and width
• Conduit type
• Usage such as control, power, spare, or abandoned
• Bend radius
• Row and column layout for conduit banks
• Routing geometry such as straight, spline, or catenary

Once placed, everything remains dynamic. If the trench depth changes, conduit count increases, or spacing needs adjustment, SDS-Physical updates the model automatically. This helps designers avoid tedious manual edits and keeps below-grade layouts aligned with the rest of the station design.

Automated Grounding Grid Creation and Validation

Grounding grids require a high degree of precision and are often one of the most time-intensive parts of substation design. SDS-Physical supports multiple methods for generating grids:

• Converting existing polylines
• Creating arrays based on user-defined spacing
• Automatically generating grids with configurable intersection distance
• Adding connections to equipment using port snapping

Designers can quickly draw a polyline, convert it into a grounding grid, and connect equipment with intelligent connectors. Validation rules ensure grounding cable sizes and clearances meet engineering and safety standards.

This blend of automation and validation reduces field errors and speeds up engineering cycles, particularly for large or complex yards.

Why Below-Grade Automation Matters

Below-grade systems may be out of sight, but they are critical to the safety and functionality of the substation. When designs rely on manual drafting, the risk of routing errors, spacing issues, and incomplete connections increases dramatically.

SDS-Physical for AutoCAD helps prevent these issues by:

• Automating repetitive and error-prone layout tasks
• Ensuring design consistency with rule-driven validation
• Keeping conductors, segments, and conduits organized in the model
• Enabling rapid updates as equipment or routes change
• Providing a clear, model-based representation of underground systems

For substation designers and engineers, these capabilities translate directly into saved time, reduced rework, and more accurate, buildable designs.

See Below-Grade Automation in Action

This post highlights just a portion of what SDS-Physical for AutoCAD can do. If your team is looking to improve accuracy, accelerate design timelines, or better manage the complexity of below-grade substation work, we’d be happy to show you more.

Contact us to schedule a demo or learn how SDS-Physical can support your substation design workflows.