ARK Engineering Solutions

CircuitCalc

Compliant

Supply

Incoming to the enclosure

L-L
V
bolted
kA
blank = 0.85×Isc
kA
°C
%
Table 22

Main bus

Pass
m
A
kA
Bus rating
450 A
CSA
300 mm²
Σ Ib
98.0 A
Isc at bus
24.5 kA

One-line

AC 415 V · 25.0 kA

Incoming250 A50×6 CU16 AQ12.5 mm² · 35 m16 AQ22.5 mm² · 28 m63 AQ316.0 mm² · 45 m32 AQ46.0 mm² · 22 m10 AQ51.5 mm² · 18 m

Outgoing circuits

Tap a row to size cable, protection and length

Q1 — Lighting — LED battens

AS/NZS 3008 sizing · AS/NZS 3000 protection & loop

Pass
A
A
kA
m
blank = supply
Selected CSA
2.5 mm²
PE
2.5 mm²
Iz derated
16.8 A
base 21 · kt 1.00 · kg 0.80
Voltage drop
1.46 %
6.04 V
Isc at origin
24.5 kA
Isc at end of line
0.69 kA
Earth-fault at end
347 A
Zs / Zs max
0.691 Ω
max 1.498 Ω · Ia 160 A
Lmax voltage drop
120 m
Lmax earth-fault loop
77 m
Governing Lmax
120 m
Recommended CSA
2.5 mm²
  • Pass

    Load vs protection

    12.0 A ≤ 16 A

    Ib 12.0 A is within In 16 A

    AS/NZS 3000 cl 2.5.3

  • Pass

    Protection vs cable CCC

    16.8 A ≥ 16 A

    In 16 A ≤ Iz 16.8 A after derating (kt 1.00 × kg 0.80)

    AS/NZS 3000 cl 2.5.3 · AS/NZS 3008

  • Pass

    Breaking capacity

    25.0 kA ≥ 24.5 kA

    Icu 25.0 kA ≥ prospective 24.5 kA at the outgoing terminals

    AS/NZS 3000 cl 2.5.4

  • Pass

    Short-circuit withstand

    2.5 mm² ≥ 1.97 mm²

    2.5 mm² ≥ 1.97 mm² required (k=115, I²t 51200 A²s)

    AS/NZS 3008 adiabatic · AS/NZS 3000 cl 5.3.3

  • Pass

    Voltage drop

    1.46 % ≤ 5.0 %

    1.46 % (6.04 V) over 35.0 m is within 5.0 %

    AS/NZS 3000 cl 3.6.2

  • Pass

    PE conductor size

    2.5 mm² ≥ 2.50 mm²

    PE 2.5 mm² meets Table 5.1 (2.5 mm²) and adiabatic (1.68 mm²)

    AS/NZS 3000 Table 5.1

  • Pass

    Earth fault loop impedance

    0.691 Ω ≤ 1.498 Ω

    Zs 0.691 Ω ≤ Zs max 1.498 Ω. 30 mA RCD also provides shock protection (cl 2.4.2) — Table 8.1 is not the sole disconnection method

    AS/NZS 3000 cl 2.4.2 / 5.7

  • Pass

    Circuit length

    35.0 m ≤ 120 m

    35.0 m is within Lmax 120 m (VD 120 m)

    AS/NZS 3000 cl 3.6 / Table 8.1

ARK Engineering Solutions

ARK Engineering Solutions

CircuitCalc

Enclosure internal fit-out calculation report

Project

MCC-01 internal fit-out

Enclosure

ENCL-A

Issued

29 October 2026

Document

CC-ENCL-A

Design status

COMPLIANT

45 pass · 0 check · 0 fail
5 outgoing circuits

1. Supply and incomer

SystemAC 3φ 415 V 50 Hz
Incoming fault level25.0 kA
Earth fault (Ief)Derived from Isc
Ambient40 °C
Design PF0.85
Voltage-drop limit5.0 %
Grouping (default)2 circuits bunched
IncomerMCCB 250 A · Icu 36 kA

2. Main bus

Construction50 × 6 mm Cu busbar
Length1.20 m
CSA300 mm²
Rating450 A
Σ Ib / diversified98.0 A / 78.4 A
Bus voltage drop0.01 % (0.02 V)
Isc at bus24.5 kA
Adiabatic Smin (0.1 s)49.7 mm²
Bus checksCOMPLIANT

3. Outgoing circuit schedule

TagLoadIbDeviceCSAPELIzVDIscZsLmaxOK
Q1Lighting — LED battensLighting12.0 AMCB Type C 16 ARCD2.5 mm²2.5 mm²35.0 m17 A1.46 %0.69 kA0.691 Ωmax 1.498120 mPass
Q2GPO circuit — workshopSocket / GPO12.0 AMCB Type C 16 ARCD2.5 mm²2.5 mm²28.0 m17 A1.16 %0.85 kA0.555 Ωmax 1.498120 mPass
Q3Pump motor DOLMotor42.0 AMCB Type C 63 A16.0 mm²16.0 mm²45.0 m64 A0.97 %3.15 kA0.144 Ωmax 0.380125 mPass
Q4VSD feeder — conveyorVSD / drive28.0 AMCCB 32 A6.0 mm²6.0 mm²22.0 m38 A0.98 %2.34 kA0.197 Ωmax 0.74988 mPass
Q524 V control / PLC (from 415 V)Control / PLC4.0 AMCB Type C 10 A1.5 mm²1.5 mm²18.0 m12 A0.41 %0.80 kA0.594 Ωmax 2.39674 mPass

Installation: In wiring enclosure unless noted on the circuit. Conductor typically Cu. Lmax is the lesser of voltage-drop and earth-fault loop limits.

4. Protection and compliance checks

All applied AS/NZS 3000 and AS/NZS 3008 checks passed for the incomer, main bus and outgoing circuits as entered.

5. Basis of calculation

  • Current-carrying capacity from AS/NZS 3008.1.1 typical Australian conditions (40 °C air unless a different ambient is entered). Ambient and grouping factors applied.
  • Protection coordination: Ib ≤ In ≤ Iz (AS/NZS 3000 cl 2.5.3). Breaking capacity Icu ≥ prospective Isc (cl 2.5.4). Short-circuit withstand S ≥ I√t / k (AS/NZS 3008 Table 52).
  • Voltage drop: 3φ √3 I L (R cosφ + X sinφ); 1φ and DC 2 I L R. Limit as entered (default 5 %, AS/NZS 3000 cl 3.6.2).
  • Earth-fault loop: Zs = Ze + Zbus + (Zph + Zpe) × L. Zs max = U0 / Ia for 0.4 s disconnection. Earth CSA from Table 5.1 and the adiabatic equation.

Prepared by

 

Checked by

 

Date

29/10/2026