Calculator guide
How to Use Conduit Calculator Pro
Use this guide to estimate conduit fill, compare available sizes, distribute low-voltage cables across multiple conduits, and create a calculation report.
1
Add project information (optional)
Open Project information to enter a project name, location, designer, calculation title, and notes. These fields do not change the calculation; they identify the work in PDF and CSV reports.
2
Select the conduit plan
- Select Edit on Conduit 1.
- Choose the conduit family and trade size.
- Use the separate chevron to collapse the row after making the selection.
- Select Add another conduit when the design includes multiple pathways.
When more than one conduit is selected, the calculator distributes the cable load across their available capacities.
3
Add the cables
- Select Edit on Cable 1.
- Choose the cable category, manufacturer, and product.
- Enter the required cable quantity.
- Select Add another cable for every additional cable type in the pathway.
The library supplies the stored outside diameter. For an unlisted product, choose Other / custom, enter its outside diameter, and optionally add a name and description for the report.
4
Choose the fill criteria
The default is Recommended low-voltage fill — 40%. Select another available method only when the applicable project criteria require it.
5
Configure bends and pulling allowance (optional)
Open Configure to enter the number of 90-degree bends or a total bend angle. The calculator can apply a telecommunications planning allowance that reduces usable capacity as the pathway becomes more difficult to pull.
This allowance is not a pulling-tension, sidewall-pressure, bend-radius, or cable-jamming analysis.
6
Review Live Results
Live Results updates as inputs change. It shows PASS or FAIL, cable quantity, fill percentage, permitted fill, and the number of selected or recommended conduits.
- PASS:the complete cable load is within the selected plan's permitted capacity.
- FAIL: the selected plan needs more capacity.
Select View results for the recommendation, allocation, cable breakdown, and mathematical details. If a recommendation is suitable, select Use this conduit plan to apply it to the inputs.
7
Review cable distribution and formulas
For a multi-conduit plan, open Show cable distribution to see the quantity assigned to each conduit, its actual fill, and its status.
Formula Details documents cable diameter and area, combined cable area, conduit internal area, permitted area, fill percentage, remaining area, and the conduit-by-conduit capacity logic.
8
Download or reset
Use Print / Save PDF for a formatted engineering report or Download CSV for spreadsheet-ready calculation data. Select Reset Calculator to begin a new calculation.
Important engineering reminder
Conduit Calculator Pro is a planning tool. Verify exact cable dimensions, pathway data, routing conditions, adopted requirements, project specifications, and installation constraints before issuing a design or beginning installation.
Common questions
Why does the selected conduit show FAIL?
FAIL means the entered cable area exceeds the permitted fill capacity of the selected conduit plan. Open the detailed results to review a larger or multi-conduit recommendation.
Why is the calculator recommending multiple conduits?
The complete cable load does not fit within the permitted capacity of one available conduit. The calculator uses the largest available trade size where needed and a smaller final conduit when it can carry the remaining cables.
What does the default 40% fill mean?
The calculator permits the cables to occupy up to 40% of the conduit internal area. This is the default low-voltage planning criterion; project requirements may call for a different limit.