Enter the load and how much of it is continuous, the conductor, the conditions, the run and the drop you will accept. The app gives the conductor, the breaker, the EGC and the conduit, says which step set the size, draws the feeder and writes a PDF.
The app’s own example, every screen in order, 16 steps.
STEP 1 OF 16The example opens filled in: a 200 A feeder, 150 A continuous, 208 V 3-phase, 250 ft, 3% drop, in EMT, the answer pinned at the foot.
STEP 2 OF 16The load: 200 A, 150 A continuous, a feeder for a general load, OCPD left to recommend, copper at 90 C.
STEP 3 OF 16Conditions: 86 F ambient, 3 current-carrying conductors per raceway, in a raceway longer than 24 in.
STEP 4 OF 16Not mostly nonlinear, so the wye neutral does not count: 3 current-carrying conductors. Not on a rooftop.
STEP 5 OF 16No part outdoors. Voltage drop: 208 V, 3-phase 4-wire, 250 ft one way, 3% maximum, Table 9 at 0.85 power factor.
STEP 6 OF 16Table 9 is the default, its Effective Z at 0.85 pf; untick it for the K method. Then parallel sets: Allow parallel is ticked.
STEP 7 OF 16Parallel sets allowed, up to 500 kcmil per set. Force parallel is off.
STEP 8 OF 16EMT, then the drawing: the circuit, a 250 A breaker, 300 kcmil copper, a 3 AWG EGC and 2-1/2 in EMT at 33.1% fill.
STEP 9 OF 16The raceway to scale, and why 300 kcmil: 250 kcmil drops 3.04%. Table 9 gives 5.63 V, 2.71%.
STEP 10 OF 16The figures: 250 A, 300 kcmil Cu, 3 AWG Cu EGC, 2-1/2 in EMT. The answer: governed by voltage drop.
STEP 11 OF 16How it was worked out: 125% of 150 A plus 50 A is 237.5 A, 3/0 fails the 3% target, upsized to 300.
STEP 12 OF 16The EGC raised to 3 AWG in proportion, the fill, 5.63 V at 250 ft. Then check one conductor size, and the report.
STEP 13 OF 16The report: save or share the PDF, or save the job. Below, the code references in plain language.
STEP 14 OF 16Code references in plain language: Chapter 9 fill, 310.15(C)(1) adjustment, ambient correction and 110.14(C).
STEP 15 OF 16The rest of the code references: 240.4(D), the rooftop adder in 310.15(B)(2), and 310.14(A)(2).
STEP 16 OF 16The PDF, page 1: every input and the answer, 300 kcmil copper with a 3 AWG copper EGC in 2-1/2 in EMT, 250 A OCPD.
The same 16 screens with the captions burned in. No sound.
MP4, 2.0 MB, 17 seconds.
The PDF report for the same job, all 3 pages as the app writes it.
On Android, $49.99 once. Everything on this page.
In the Suite as part of its Conduit Fill screen, split out here. The app's corrections to the figures (240.4 checked on derated ampacity, the EGC raised only for voltage-drop upsizing, voltage drop worked for the final size, the rooftop adder) and the vertical feeder drawing are being brought back across.
