Pull Box Sizing

From input to answer.

Set the region to Canada and open All Tools → Pull Box Sizing.
Add the pull type and conduit entries. Confirm trade sizes and connected entry pairs.
Set box dimensions and entry positions. Enter actual fitting envelopes and inward projections where requested.
Review all fit and clearance checks, including the fitting details. Resolve warnings before using the layout.

WORKED EXAMPLE

Why internal clearance matters

Enter

For a straight pull using trade size 53, the model requires 424 mm clear distance. If each opposing fitting projects 10 mm inward, a 444 mm internal width leaves 424 mm between them.

Read the result

444 − 10 − 10 = 424 mm. A 400 mm internal width would leave only 380 mm. This illustrates that one clearance check; all other box, entry and fitting checks must also pass.

Get more from it.

Use internal usable dimensions rather than catalogue outside dimensions.
A nominal trade size is not a fitting’s outside envelope. Enter the actual fitting data.

Know the limits.

CEC 2024 supported straight, angle and U-pull checks; not a complete enclosure or installation approval.
Cable bend radius, splices, accessibility, usable depth and actual drilling/fitting constraints need independent review.

Verify the inputs, applicable local requirements and real conditions. The app is a calculation aid and can contain errors. See our terms and safety disclaimer.

Common questions.

Does one green clearance result approve the whole box?

No. Review every applicable check and actual fitting geometry.