Underground Raceway Analysis

Ductbank Route

Build conduit layouts, assign cables, and run NEC fill plus thermal checks from one workspace.

1. Validate 2. Fill 3. Thermal 4. Export
Method & Assumptions

Thermal resistance is evaluated as R = ln(D_e/D_i)/(2πk).

Variables:

  • D_e – external diameter
  • D_i – internal diameter
  • k – thermal resistivity

Citations: IEEE 835

Applicability: homogeneous soil and steady-state current.

See also: Load Calculation Formulas, Cable Fill Rules, Routing Assumptions.

0 Conduits
0 Cables
0 Assigned
0 Unassigned
0 Warnings
0 Thermal Alerts
0 Ampacity Alerts

Ductbank Setup

Set the route tag, burial depth, and encasement assumptions used by the drawing and thermal checks.

Ductbank Conduits

Define each conduit and let the layout controls position the bank consistently.

0 conduits
ID Type Trade Size X Y Dup Del

Cables

Assign each cable to a ductbank conduit and provide the fields needed for fill and ampacity checks.

0 cables
Tag Type Diameter (in) Cond. Size Insul. Thick (in) Weight Est. Load (A) Conduit Conductor Material Insulation Type Insul. Rating (°C) Voltage Rating Shielding / Jacket Type Dup Del
Thermal Parameters Soil, spacing, and solver assumptions
Typical Soil Properties
Soil TypeThermal Resistivity (°C·cm/W)
ConditionMoisture Content (%)
Dry2–5
Damp5–10
Moist10–20
Wet / Saturated20+

Drawing & Analysis

Review conduit fill, cable placement, thermal overlays, and ampacity estimates.

Ampacity Estimates