Panel Groups
Panel groups are the organizational unit for string solving in Branch. Understanding how they work helps you get better results from the solver.
What are Panel Groups?
A panel group is a collection of solar panels that Branch organizes together based on geometric alignment and proximity. Each panel group is solved independently by the string solver.
Panel groups are similar to the industry term sub-arrays, but with one key difference: a panel group can include panels from adjacent sub-arrays if those panels share a string with panels in this group. When you use the ADDPANELS command to transfer panels between groups (connected by jumper cables), the transferred panels become part of the target panel group even though they physically belong to a different sub-array.
Why Panel Groups Matter
The string solver works on one panel group at a time. Panels in the same group can be connected into strings together. Panels in different groups require jumper cables to connect them.
How Branch Detects Panel Groups
When you run PANELGROUPCREATE, Branch analyzes your drawing and groups panels based on three criteria:
1. Rotation Angle
Panels must face the same direction (same rotation angle) to be grouped together. This ensures panels in a row are aligned for proper string routing.
2. Proximity (Max Panel Gap)
Panels must be within the Max Panel Gap distance of each other. Larger gaps create separate groups. Adjust this setting in BRANCHOPTIONS if your groups are too large or too fragmented.
3. Alignment Tolerance
Panels in the same row can have slight misalignment (due to CAD precision or terrain). The Alignment Tolerance setting controls how much misalignment is allowed before panels are considered separate rows.
Panel Group Labels
Each panel group displays a header label showing:
- +NAdd N panels to get even string lengths
- -NRemove N panels to get even string lengths
- ✓Panel count already divides evenly by your string length
These recommendations are based on your configured string length. Use them as a guide when balancing panels across groups with the ADDPANELS command.
Modifying Panel Groups
ADDPANELSTransfer panels from one group to another. Select the target group, then select the panels to transfer. This is how you balance panel counts for even strings.
When you run SOLVE after adding panels, you'll be prompted to indicate where the jumper cable connects the transferred panels to their new group.
REMOVEPANELRemove panels from a group entirely. Use this to exclude panels that shouldn't be part of the electrical design (e.g., placeholder panels, panels to be removed).
Re-creating Panel Groups
If you need to start over, you can run PANELGROUPCREATE again. This will delete existing panel groups and create new ones based on current settings.
Configuration Options
These settings in BRANCHOPTIONS affect how panel groups are created and displayed:
| Setting | Description |
|---|---|
| Max Panel Gap | Maximum distance between panels to include them in the same group |
| Alignment Tolerance | Allowable misalignment between panels in the same row |
| Extract from Rack Blocks | Whether to extract individual panels from racking block definitions |
| Panel Group Layer | AutoCAD layer for panel group outlines |
| Label Height | Text height for the +/- header labels |
| Outline Width | Line width for panel group boundary polylines |
| Hide Outlines | Hide panel group outlines to reduce visual clutter |