Why tray fittings need a separate takeoff
Straight tray length does not describe the complete accessory requirement. Joints need connection hardware, direction changes may require elbows, branches may require tees, width changes may require reducers, and support points require their own hardware.
Calculation model
The tool converts each feature into an accessory quantity using your supplied rules. For example, if 40 straight sections create 39 internal joints and one coupler is required at each joint, the modeled coupler quantity is 39.
Elbows, tees and reducers are counted directly. Connector and support-kit quantities are then derived from the configured per-feature rules.
Why rules are configurable
Tray accessory systems vary by manufacturer and installation method. Hard-coding a universal fitting package would create false precision, so the planner exposes the relationships as user inputs.
Worked example
With 40 straight sections, there are 39 internal joints. At one coupler per joint, 39 couplers are needed. Four elbows requiring two connectors each produce eight connector units. Twenty-one support points at one kit each produce 21 support kits in the planning model.
Interpretation
The result is a material-takeoff structure, not a manufacturer's bill of materials. Confirm the actual fitting compatibility and hardware package for the selected tray system.
Limitations and safety
The tool does not determine tray structural capacity, loading, support spacing, seismic requirements, corrosion environment or product-specific fittings. Those decisions must come from the selected system and project design.
Frequently asked questions
How are couplers calculated?
Internal straight-section joints are modeled as section count minus one, multiplied by the coupler-per-joint input.
Can an elbow require more than one connector?
Yes. Enter the connector relationship appropriate to your product system.
Does the planner select fitting models?
No. It creates quantities only.