4. Mechanical Layout

Once all site objects have been defined, the Mechanical Layout tab is where the primary design of your solar array begins. This tab allows you to select your modules, choose a mounting system, and define the structural configuration of your project. The Mechanical Layout tab is also where you generate the initial arrangement of your blocks of modules based on project constraints, available areas, and design preferences. You will make additional adjustments to this layout based on your Topography on the Topography and Reports tab.

If your project includes multiple installation areas, you can utilize the Subarray tool at the bottom of the window. This allows you to assign different modules and racking configurations to each defined subarea independently.

Mounting System

Select the type of mounting system appropriate for your project:

Choose from 1-Axis, Fixed, or Fixed EW (east-west) racking types.
Use either a User Defined system or a preloaded manufacturer system such as NEXTracker or Array Technologies.
- If you select User Defined, you’ll be able to manually configure: parameters that define the structural layout

Using the SAVE CONFIG you can save the standard block and configuration you have defined on the Mechanical tab for future projects. If you have already saved a configuration, you can simply click LOAD CONFIG and quickly load up the same format layout for your new project.

Module

Choose the module type to use for this layout, the INFO button will show you the specifications. The modules in our database include PAN files for detailed energy modeling.

Select from an extensive database of preloaded manufacturer modules
If your desired module is not listed, you may:
- Upload a custom module to the database by DATABASE button in the PVCAD ribbon to add modules locally (note: this will only add the module locally)
- Contact the PVCAD support team to request inclusion of a missing module at support@pvcomplete.com and we will add within 24 hours for all PVCAD users

Layout

Define the spacing parameters between each of the structures in your lay out. Each input unit is defined by the units you have set. Hovering your mouse will show you diagrams for the meaning of each input cell. Depending on whether you are using fixed tilt, EW or 1-axis tracker, the options in this section may change. In this section you will set key values including:

GCR (Ground Coverage Ratio) or Row Spacing or Pitch (note: only need set one of these values and others will populate automatically)
Column Gap – This is space between tracker columns
Structure Length – This relates to the number strings allowed in your trackers and the allowance of partials – we allow up three string quantity options for full and partial trackers
- Structure length will determine the layout density of your system as you deal with full trackers approaching your boundary line

Structure Design

Customize the tracker or fixed tilt structure before you lay it out across the project site. Hovering your mouse will show you diagrams for the meaning of each input cell. Depending on whether you are using fixed tilt, EW or 1-axis tracker, the options in this section may change. In this section you will set key values including:

Orientation – Select landscape or portrait orientation of modules on your tracker
Row Quantity – Define how many modules you have in each row of your tracker
Column Gap – This is the space between columns of modules in your tracker
Motor Gap – Space reserved for your tracker motor, you can select the exact location of your motor by clicking the PIER DISTANCES button and defining the location for each full and partial tracker
Pier Qty – This is the number of piers or piles for your full tracker system
String Length – The number of modules that are connected in series
String Qty – This is the number of strings that you have for the full tracker and is directly related to the Structure Length you defined for your full and partials
Stickout – The length of additional structure that extends past the last module column for each tracker, under PIER DISTANCES this can be defined differently for your North or South stickout
Bearing Gap – Bearing gap is the distance between support bearings for your tracker
T Tube Stickout – T-Tube stickout (or torque tube stickout) refers to the portion of the torque tube—the rotating shaft that holds and moves solar modules in a single-axis tracker system—that extends beyond the last module at either end of the tracker row.

When using preloaded manufacturer systems, customization options may be limited to maintain alignment with vendor specifications. Using the PIER DISTANCES button you can set specific arrangement of your structure, and add or remove strings. PVCAD Mega will automatically calculate your Structure Length and Structure Width as you adjust your structure.

Access Roads and Equipment Pads

Using this section you can customize a standard block. If you would like to simply max fill or click and drag your layout with the Structure and Layout settings you have, you can skip this section. If you want to utilize this section – click INSERT INSTALL AREAS when you are ready to layout your system. Here are the options you have in setting up your standard block.

Standard Block Setup – Input the number of tracker structures for your Standard Block you want in the east-west (EW) and north-south (NS) directions
- Listed below is the Width and Length of your block calculated based on your number of trackers inputted in each direction
Standard Block Layout Options – Choose between Max Fill (which allows partial blocks to increase total DC capacity) or Standard Fill (which uses only complete blocks) – see an example by clicking INFO
Road Setup – Define space allocation for EW and NS roadways for O&M access. If you want roads only in one direction, simply mark zero in either of the input cells in this section. See an example of the orientation by clicking INFO
Equipment Pad: Set pad dimensions and specify its location relative to the block (e.g., center, edge). You can mirror the pad placement for adjacent tracker blocks by checking the box. Meaning if the block is placed in the Northwest corner of a block, the adjacent block will be placed in the Southwest corner.

Making the Layout

You can generate the physical layout of modules using several different tools:

MAKE LAYOUT: Automatically fills the selected installation area with modules, factoring in the chosen mounting system, spacing, azimuth, and obstructions. Click the button, select your installation area in the drawing, and choose an azimuth angle.
CLICK & DRAG: Manually place trackers or fixed racks in various sections of your site according to your structure and layout design by clicking and dragging inside the installation area
INSERT INSTALL AREAS: Populates your project using the Standard Block configuration defined earlier, choose between Max Fill with partial blocks or regular fill with whole blocks within the Standard Block Layout Options
ADD TABLE: Manually insert tracker tables that snap into alignment with your design

Additional Mechanical Layout Tools

The sections and tools below will help you further specialize and configure your layout.

Subarray – PVCAD Mega allows you to make multiple subarrays within a project that can have its own defined mounting or module configuration. After you have defined installation areas in your site objects tab – use this Subarray section to select, HIGHLIGHT, or DELETE the subarray int he Current drop down. Once selected – you can make adjustments to this subarray on the Mechanical Layout tab without impacting other subarrays.
Layout Preferences – Set a maximum DC system size constraint before initiating your layout generation, this is perfect if you are constrained to a maximum output or interconnection capacity.
WIND EXPOSURE– Identify and categorize interior vs. exterior trackers in your layout; this distinction is reflected in the Bill of Materials
ASSIGN BLOCKS– Replace automatically generated blocks with your custom blocks. Click this button, select the existing block to be replaced, and then choose the new custom block

This completes the configuration and layout process. Once finished, proceed to Topo & Reports tab to incorporate topography adjustments into your design.