Motor Cable Selection Chart

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AS/NZS 3008 edition

The calculation and its reports use the AS/NZS 3008.1.1:2017 tables.

Power factor direction

Supply voltage (V) *

Running power factor

Motor efficiency

Applied to every kW row: I_FL = P / (√3 V cosφ η)

Starting method

Starting current multiple

Starting power factor

0 = use the starting method's multiple (DOL 6, Star-Delta 2, Soft-start 3, VSD 1.5). Starting PF is typically 0.2–0.4 for DOL.

Design factor

I_B = I_FL × design factor; AS/NZS 3000 motor default 1.25

Running Vd limit

Starting Vd limit

Running drop at I_FL; starting drop at the starting current and starting PF

Smallest motor (kW) *

Largest motor (kW) *

IEC 60072 preferred ratings; one chart row per rating in the range

Smallest size (mm²) *

Largest size (mm²) *

One chart column per standard size in the range; sizes the tables do not list for this cable are greyed out

Parallel sizes (mm²)

Cables per phase

Comma-separated sizes to add as parallel-cable columns (blank = none). Parallel sets share the fault current equally and take no extra grouping derating.

Earth conductor

Sets the earth used for the earth-fault loop and the earth-conductor checks in every column

Maximum displayed length

Cells above this show "> N" rather than an impractical run length

Cable type

Cable formation

Multicore arrangement

Singlecore arrangement

Cable insulation

Conductor material

Installation method

Unenclosed type (MC)

Unenclosed type (SC)

Air arrangement

Catinerary

Cables per tier

Circuits per tier

Ladder spacing

Ladder tiers

Bunched circuits/cables

Bunched arrangement

Thermal ins coverage

Thermal ins method

Enclosed type

Conduit spacing

SC conduit type

Direct buried spacing

Buried circuits/cables

Air ambient temperature (°C)

Burial depth (m)

Soil ambient temperature (°C)

Soil resistivity (K·m/W)

Device type

Instantaneous trip multiplier

Rating per row = smallest standard rating ≥ I_B. 0 = device default (gM 5 × I_N, MCCB 10 × I_N) for the earth-fault loop check.

Prospective fault current

SC clearing time

Short-circuit withstand is checked per size; failing sizes are flagged in the column header

Earth fault clearing time

Earth-conductor withstand: instantaneous operating time, or upstream backup time if relied on

Source impedance

Upstream loop impedance Z_s at the cable origin; sets the EFL length limit

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Calculation No.: Calc-001
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Motor Cable Selection Chart

A selection chart for one installation condition: rows are preferred motor ratings with their automatically selected protective device, columns are conductor sizes with their derated current-carrying capacity I_Z. Each cell is the longest cable run the motor may be supplied over, the smallest of three lengths: the running voltage drop, the starting voltage dip and the earth fault loop impedance that still lets the device disconnect. Cable data per AS/NZS 3008.1.1:2017; disconnection and earth conductor size per AS/NZS 3000:2018 Appendix B5 and Table 5.1. Grey cells are not applicable (cable rating below the design current, no device rating, or a size not tabulated); yellow cells are governed by the earth fault loop or sit in a column whose size fails the short-circuit or earth-conductor checks; red column headers mark those failing sizes.

1.1 Supply & Motor Basis

Supply, motor and voltage-drop basis common to every row:

Parameter	Symbol	Value	Notes
AS/NZS 3008 Edition		2017	The only supported edition
Power Factor Direction		lagging	Sign of the reactive voltage-drop term
Supply Voltage	V	400 V	Line-to-line, three phase
Power Factor	cosφ	0.85	Running, full load
Motor Efficiency	η	95 %	IEC 60072 ratings are shaft output
Starting Method		DOL
Starting Current Multiple	k_start	6 × I<sub>FL</sub>	Used for DOL
Starting Power Factor	cosφ_start	0.35
Design Factor	k_design	1.25	I<sub>B</sub> = k<sub>design</sub> × I<sub>FL</sub>
Maximum Running Voltage Drop	V_d,max	5 %
Maximum Starting Voltage Dip	V_d,start	15 %

1.2 Cable

Cable construction; the conductor size varies by column:

Parameter	Symbol	Value	Notes
Cable Type		Fixed	Cable construction
Cable Formation		Multicore	Multicore or Singlecore
MC Arrangement		Circular	Conductor arrangement
Cable Insulation		XLPE	Insulation type
Conductor Material	Material	Cu	Cu or Al
Earth Conductor		AS/NZS 3000 Table 5.1 minimum	Per column; shown under each size
Resistance Temperature	θ_R	90 °C	Conductor operating temperature for R<sub>c</sub>

1.3 Installation

Installation method and environmental conditions:

Parameter	Value	Notes
Installation Method	Unenclosed
Unenclosed Type (MC)	Spaced from Surface
Air Arrangement	Perforated Trays Horizontal
Cables Per Tier	1
Ladder Spacing	Spaced
Ladder Tiers	1Tier
Air Ambient Temp	40
Cables per Tier	1
Derating Table	D24	AS/NZS 3008.1.1:2017

1.4 Protection

Device type, trip multiplier, fault level and clearing times:

Parameter	Symbol	Value	Notes
Device Type		gM	Rating auto-selected per row: smallest standard I_N ≥ I_B
Instantaneous Trip Multiplier	k_mag	5 × I<sub>N</sub>	Disconnection current I<sub>a</sub> = k<sub>mag</sub> × I<sub>N</sub>
Prospective Fault Current	I_f	10 kA
Protection Clearing Time	t_prot	100 ms	Short-circuit withstand
Earth Fault Clearing Time	t_ef	40 ms	Near-end earth fault (earth withstand)
Source Impedance	Z_s	100 mΩ	Upstream loop impedance

1.5 Chart Extents

Motor ratings and conductor sizes covered by the chart:

Parameter	Symbol	Value	Notes
Motor Range		0.37 – 185	24 preferred ratings
Conductor Range		2.5 – 185	14 columns incl. parallel
Parallel Sizes		95	2 cables in parallel
Display Cap	L_cap	500 m	Longer lengths shown as "> cap"

2. Method

Every cell is worked from the motor rating and the per-size cable data. Lengths are in metres; R and X are AS/NZS 3008.1.1 per-kilometre values (already divided by the number of cables for parallel columns). Resistances are read at the insulation operating temperature (PVC 75 °C, XLPE 90 °C, EPR 110 °C; aluminium capped at 90 °C).

2.1 Full Load Current

Line current of a three-phase motor of shaft output P (kW):

Formula: $$ I_{FL} = \frac{P \times 1000}{\sqrt{3} \, V \cos\varphi \, \eta} $$

2.2 Starting Current

k_start from the starting method unless overridden.

Formula: $$ I_{start} = k_{start} \times I_{FL} $$

2.3 Design Current and Device

I_N is the smallest standard device rating not less than the design current.

Formula: $$ \begin{aligned} I_B &= k_{design} \times I_{FL} \qquad I_N \\ &= \min\{ I_{N,std} \geq I_B \} \end{aligned} $$

2.4 Disconnection Current

Earth-fault current that must flow for automatic disconnection (AS/NZS 3000:2018 B5).

Formula: $$ I_a = k_{mag} \times I_N $$

2.5 Running Voltage-Drop Length

Formula: $$ L_{run} = \frac{V_{d,max}/100 \times V}{\sqrt{3} \, I_{FL} \, \left| R_c \cos\varphi + X_c \sin\varphi \right|} \times 1000 $$

2.6 Starting Voltage-Dip Length

Same as the running length with the starting current, starting power factor and starting dip limit.

Formula: $$ L_{start} = \frac{V_{d,start}/100 \times V}{\sqrt{3} \, I_{start} \, \left| R_c \cos\varphi_{s} + X_c \sin\varphi_{s} \right|} \times 1000 $$

2.7 Earth Fault Loop Length

V_ph = V/√3; |Z_c| = √(R_c² + X_c²) and |Z_e| = √(R_e² + X_e²) in Ω/km. Magnitudes are added arithmetically, an upper bound on the phasor sum.

Formula: $$ L_{efl} = \frac{V_{ph}/I_a - Z_s}{|Z_c| + |Z_e|} \times 1000 $$

2.8 Cable Loading

A cell is blank when the loading exceeds 100 % (cable rating below I_B) or no device rating fits.

Formula: $$ \text{loading} = \frac{I_B}{I_Z} \times 100 \; \% $$

2.9 Maximum Length

The argument of the minimum is the governing limit; a cell is shaded yellow when the earth fault loop governs or the size fails a length-independent check.

Formula: $$ L = \min(L_{run}, L_{start}, L_{efl}) $$

2.10 Worked Cell

The first usable cell of the chart, a 0.37 kW motor on 2.5 mm² (row 1, column 1): I_FL 0.7 A, I_start 4.0 A, I_N 6 A, I_a 30 A; R_c 9.450, X_c 0.09880, R_e 9.450, X_e 0.09880 Ω/km.

2.11 Running Voltage-Drop Length

Formula: $$ \begin{aligned} L_{run} &= \frac{5/100 \times 400}{\sqrt{3} \times 0.6614 \times |9.450 \times 0.85 + 0.09880 \times 0.5268|} \times 1000 \\ &= 2160 \; \text{m} \end{aligned} $$

2.12 Starting Voltage-Dip Length

Formula: $$ \begin{aligned} L_{start} &= \frac{15/100 \times 400}{\sqrt{3} \times 3.97 \times |9.450 \times 0.35 + 0.09880 \times 0.9367|} \times 1000 \\ &= 2568 \; \text{m} \end{aligned} $$

2.13 Earth Fault Loop Length

Formula: $$ \begin{aligned} L_{efl} &= \frac{231/30.0 - 0.10000}{9.451 + 9.451} \times 1000 \\ &= 402 \; \text{m} \end{aligned} $$

2.14 Maximum Length

Governed by EFL. Loading I_B / I_Z = 3 %.

Formula: $$ \begin{aligned} L &= \min(2160, 2568, 402) \\ &= 402 \; \text{m} \end{aligned} $$

3. Cable Data per Size

Derated capacity, impedances, adiabatic k and the length-independent checks for each column (SC = short-circuit withstand, ESZ = earth conductor size, EWT = earth conductor withstand). Parallel columns carry n × I_Z and R, X divided by n.

Parameter	Symbol	Value	Notes
2.5 mm²	I_Z	27.0	earth 2.5 mm², Rc 9.450 / Xc 0.099 Ω/km (earth Re 9.450 / Xe 0.099), F 1.000, k 143, SC FAIL · ESZ PASS · EWT FAIL
4 mm²	I_Z	36.0	earth 2.5 mm², Rc 5.880 / Xc 0.093 Ω/km (earth Re 9.450 / Xe 0.099), F 1.000, k 143, SC FAIL · ESZ PASS · EWT FAIL
6 mm²	I_Z	46.0	earth 2.5 mm², Rc 3.930 / Xc 0.089 Ω/km (earth Re 9.450 / Xe 0.099), F 1.000, k 143, SC FAIL · ESZ PASS · EWT FAIL
10 mm²	I_Z	66.0	earth 4 mm², Rc 2.330 / Xc 0.084 Ω/km (earth Re 5.880 / Xe 0.093), F 1.000, k 143, SC FAIL · ESZ PASS · EWT PASS
16 mm²	I_Z	87.0	earth 6 mm², Rc 1.470 / Xc 0.081 Ω/km (earth Re 3.930 / Xe 0.089), F 1.000, k 143, SC FAIL · ESZ PASS · EWT PASS

Parameter	Symbol	Value	Notes
25 mm²	I_Z	116.0	earth 6 mm², Rc 0.927 / Xc 0.081 Ω/km (earth Re 3.930 / Xe 0.089), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
35 mm²	I_Z	144.0	earth 10 mm², Rc 0.669 / Xc 0.079 Ω/km (earth Re 2.330 / Xe 0.084), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
50 mm²	I_Z	182.0	earth 16 mm², Rc 0.494 / Xc 0.075 Ω/km (earth Re 1.470 / Xe 0.081), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
70 mm²	I_Z	230.0	earth 25 mm², Rc 0.343 / Xc 0.074 Ω/km (earth Re 0.927 / Xe 0.081), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
95 mm²	I_Z	275.0	earth 25 mm², Rc 0.248 / Xc 0.072 Ω/km (earth Re 0.927 / Xe 0.081), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS

Parameter	Symbol	Value	Notes
120 mm²	I_Z	327.0	earth 35 mm², Rc 0.197 / Xc 0.071 Ω/km (earth Re 0.669 / Xe 0.079), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
150 mm²	I_Z	375.0	earth 50 mm², Rc 0.160 / Xc 0.072 Ω/km (earth Re 0.494 / Xe 0.075), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
185 mm²	I_Z	428.0	earth 70 mm², Rc 0.129 / Xc 0.072 Ω/km (earth Re 0.343 / Xe 0.074), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS
2 × 95 mm²	I_Z	550.0	earth 25 mm², Rc 0.124 / Xc 0.036 Ω/km (earth Re 0.464 / Xe 0.040), F 1.000, k 143, SC PASS · ESZ PASS · EWT PASS

4. Motor Data per Rating

Full load, starting and design currents with the selected device and its disconnection current:

Parameter	Symbol	Value	Notes
0.37 kW	I_FL	0.7	I_start 4.0 A, I_B 0.8 A, I_N 6 A, I_a 30 A
0.55 kW	I_FL	1.0	I_start 5.9 A, I_B 1.2 A, I_N 6 A, I_a 30 A
0.75 kW	I_FL	1.3	I_start 8.0 A, I_B 1.7 A, I_N 6 A, I_a 30 A
1.1 kW	I_FL	2.0	I_start 11.8 A, I_B 2.5 A, I_N 6 A, I_a 30 A
1.5 kW	I_FL	2.7	I_start 16.1 A, I_B 3.4 A, I_N 6 A, I_a 30 A

Parameter	Symbol	Value	Notes
2.2 kW	I_FL	3.9	I_start 23.6 A, I_B 4.9 A, I_N 6 A, I_a 30 A
3 kW	I_FL	5.4	I_start 32.2 A, I_B 6.7 A, I_N 10 A, I_a 50 A
4 kW	I_FL	7.1	I_start 42.9 A, I_B 8.9 A, I_N 10 A, I_a 50 A
5.5 kW	I_FL	9.8	I_start 59.0 A, I_B 12.3 A, I_N 13 A, I_a 65 A
7.5 kW	I_FL	13.4	I_start 80.4 A, I_B 16.8 A, I_N 20 A, I_a 100 A

Parameter	Symbol	Value	Notes
11 kW	I_FL	19.7	I_start 118.0 A, I_B 24.6 A, I_N 25 A, I_a 125 A
15 kW	I_FL	26.8	I_start 160.9 A, I_B 33.5 A, I_N 40 A, I_a 200 A
18.5 kW	I_FL	33.1	I_start 198.4 A, I_B 41.3 A, I_N 50 A, I_a 250 A
22 kW	I_FL	39.3	I_start 235.9 A, I_B 49.2 A, I_N 50 A, I_a 250 A
30 kW	I_FL	53.6	I_start 321.7 A, I_B 67.0 A, I_N 80 A, I_a 400 A

Parameter	Symbol	Value	Notes
37 kW	I_FL	66.1	I_start 396.8 A, I_B 82.7 A, I_N 100 A, I_a 500 A
45 kW	I_FL	80.4	I_start 482.6 A, I_B 100.5 A, I_N 125 A, I_a 625 A
55 kW	I_FL	98.3	I_start 589.9 A, I_B 122.9 A, I_N 125 A, I_a 625 A
75 kW	I_FL	134.1	I_start 804.4 A, I_B 167.6 A, I_N 200 A, I_a 1,000 A
90 kW	I_FL	160.9	I_start 965.2 A, I_B 201.1 A, I_N 250 A, I_a 1,250 A

Parameter	Symbol	Value	Notes
110 kW	I_FL	196.6	I_start 1,179.7 A, I_B 245.8 A, I_N 250 A, I_a 1,250 A
132 kW	I_FL	235.9	I_start 1,415.7 A, I_B 294.9 A, I_N 315 A, I_a 1,575 A
160 kW	I_FL	286.0	I_start 1,716.0 A, I_B 357.5 A, I_N 400 A, I_a 2,000 A
185 kW	I_FL	330.7	I_start 1,984.1 A, I_B 413.4 A, I_N 500 A, I_a 2,500 A

Motor (kW)	gM (A)	2.5	4	6	10	16	25	35	50	70	95	120	150	185	2 × 95
Motor (kW)	gM (A)	27 A	36 A	46 A	66 A	87 A	116 A	144 A	182 A	230 A	275 A	327 A	375 A	428 A	550 A
0.37	6	402	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
0.55	6	402	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
0.75	6	402	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
1.1	6	402	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
1.5	6	402	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
2.2	6	363	496	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
3	10	239	295	338	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
4	10	200	295	338	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
5.5	13	145	225	258	420	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
7.5	20	107	144	165	269	409	454	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
11	25	73	114	131	213	323	359	> 500	> 500	> 500	> 500	> 500	> 500	> 500	> 500
15	40		69	79	128	195	217	351	> 500	> 500	> 500	> 500	> 500	> 500	> 500
18.5	50			62	100	152	169	274	418	> 500	> 500	> 500	> 500	> 500	> 500
22	50				100	152	169	274	418	> 500	> 500	> 500	> 500	> 500	> 500
30	80					88	98	159	242	373	402	> 500	> 500	> 500	> 500
37	100					67	74	120	184	282	304	410	> 500	> 500	> 500
45	125						55	90	137	210	227	305	399	> 500	453
55	125							90	137	210	227	305	399	> 500	453
75	200								66	102	110	148	194	263	220
90	250									66	71	96	126	170	143
110	250										71	96	126	170	143
132	315											53	69	94	78
160	400												23	31	26
185	500													0	0

Maximum length = min(running Vd, starting Vd, earth fault loop) in metres; hover a cell for all three. Cu XLPE Multicore Fixed; Unenclosed (derating table D24); 400 V, cosφ 0.85, η 95 %; Vd 5 % running / 15 % starting; gM k_mag 5, Z_s 0.1 Ω.

not applicable (cable rating below I_B, no device, or untabulated)
earth-fault loop governs or size fails SC/earth checks
size fails a length-independent check
> 500 = beyond display cap

Motor (kW)	gM (A)	2.5	4	6	10	16	25	35	50	70	95	120	150	185	2 × 95
Motor (kW)	gM (A)	27 A	36 A	46 A	66 A	87 A	116 A	144 A	182 A	230 A	275 A	327 A	375 A	428 A	550 A
0.37	6	3	2	2	1	1	1	1	0	0	0	0	0	0	0
0.55	6	5	3	3	2	1	1	1	1	1	0	0	0	0	0
0.75	6	6	5	4	3	2	1	1	1	1	1	1	0	0	0
1.1	6	9	7	5	4	3	2	2	1	1	1	1	1	1	0
1.5	6	12	9	7	5	4	3	2	2	1	1	1	1	1	1
2.2	6	18	14	11	7	6	4	3	3	2	2	2	1	1	1
3	10	25	19	15	10	8	6	5	4	3	2	2	2	2	1
4	10	33	25	19	14	10	8	6	5	4	3	3	2	2	2
5.5	13	46	34	27	19	14	11	9	7	5	4	4	3	3	2
7.5	20	62	47	36	25	19	14	12	9	7	6	5	4	4	3
11	25	91	68	53	37	28	21	17	14	11	9	8	7	6	4
15	40	124	93	73	51	39	29	23	18	15	12	10	9	8	6
18.5	50	153	115	90	63	48	36	29	23	18	15	13	11	10	8
22	50	182	137	107	74	57	42	34	27	21	18	15	13	11	9
30	80	248	186	146	102	77	58	47	37	29	24	20	18	16	12
37	100	306	230	180	125	95	71	57	45	36	30	25	22	19	15
45	125	372	279	219	152	116	87	70	55	44	37	31	27	23	18
55	125	455	341	267	186	141	106	85	68	53	45	38	33	29	22
75	200	621	465	364	254	193	144	116	92	73	61	51	45	39	30
90	250	745	559	437	305	231	173	140	110	87	73	61	54	47	37
110	250	910	683	534	372	283	212	171	135	107	89	75	66	57	45
132	315	1092	819	641	447	339	254	205	162	128	107	90	79	69	54
160	400	1324	993	777	542	411	308	248	196	155	130	109	95	84	65
185	500	1531	1148	899	626	475	356	287	227	180	150	126	110	97	75

Loading = I_B / I_Z × 100 % with I_B = k_design × I_FL. Cu XLPE Multicore Fixed; Unenclosed (derating table D24); 400 V, cosφ 0.85, η 95 %; Vd 5 % running / 15 % starting; gM k_mag 5, Z_s 0.1 Ω.

loading above 100 % (cable rating below I_B), no device, or untabulated
size fails a length-independent check

7. Size Checks

Short-circuit withstand (adiabatic, AS/NZS 3008 Table 52), AS/NZS 3000 Table 5.1 earth size and earth conductor withstand for each available size. These do not depend on length.

Parameter	Value	Notes
2.5 mm²	FAIL	SC: t_max 0.001 s vs t 0.1 s, S_min 22.1 mm² — FAIL; ESZ: earth 2.5 vs Table 5.1 minimum 2.5 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — FAIL (fails: Short Circuit, Earth Conductor Withstand)
4 mm²	FAIL	SC: t_max 0.003 s vs t 0.1 s, S_min 22.1 mm² — FAIL; ESZ: earth 2.5 vs Table 5.1 minimum 2.5 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — FAIL (fails: Short Circuit, Earth Conductor Withstand)
6 mm²	FAIL	SC: t_max 0.007 s vs t 0.1 s, S_min 22.1 mm² — FAIL; ESZ: earth 2.5 vs Table 5.1 minimum 2.5 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — FAIL (fails: Short Circuit, Earth Conductor Withstand)
10 mm²	FAIL	SC: t_max 0.020 s vs t 0.1 s, S_min 22.1 mm² — FAIL; ESZ: earth 4 vs Table 5.1 minimum 4 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS (fails: Short Circuit)
16 mm²	FAIL	SC: t_max 0.052 s vs t 0.1 s, S_min 22.1 mm² — FAIL; ESZ: earth 6 vs Table 5.1 minimum 6 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS (fails: Short Circuit)

Parameter	Value	Notes
25 mm²	PASS	SC: t_max 0.128 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 6 vs Table 5.1 minimum 6 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
35 mm²	PASS	SC: t_max 0.251 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 10 vs Table 5.1 minimum 10 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
50 mm²	PASS	SC: t_max 0.511 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 16 vs Table 5.1 minimum 16 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
70 mm²	PASS	SC: t_max 1.002 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 25 vs Table 5.1 minimum 25 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
95 mm²	PASS	SC: t_max 1.846 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 25 vs Table 5.1 minimum 25 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS

Parameter	Value	Notes
120 mm²	PASS	SC: t_max 2.945 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 35 vs Table 5.1 minimum 35 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
150 mm²	PASS	SC: t_max 4.601 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 50 vs Table 5.1 minimum 50 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
185 mm²	PASS	SC: t_max 6.999 s vs t 0.1 s, S_min 22.1 mm² — PASS; ESZ: earth 70 vs Table 5.1 minimum 70 mm² — PASS; EWT: S_min 3.23 mm² at I_ef 2,309 A, t_ef 0.04 s — PASS
2 × 95 mm²	PASS	SC: t_max 7.382 s vs t 0.1 s, S_min 11.1 mm² — PASS; ESZ: earth 25 vs Table 5.1 minimum 25 mm² — PASS; EWT: S_min 1.61 mm² at I_ef 1,155 A, t_ef 0.04 s — PASS

8. Summary

Chart coverage and governing limits:

Parameter	Value	Notes
Chart Size	24 × 14	motor ratings × size columns
Motor Range	0.37 – 185
Conductor Range	2.5 – 185	parallel: 95
Sizes Available	14 of 14	tabulated for this installation
Usable Cells	254 of 336	240 flagged, 148 beyond the display cap
Governing Limit	run 5 · start 14 · EFL 235	usable cells by governing limit
Sizes Failing Checks	2.5, 4, 6, 10, 16	short circuit / earth size / earth withstand
Overall Status	PASS	PASS when at least one cell is usable

9. Warnings & Recommendations

Warnings:
  Sizes failing a length-independent check (flagged across the column): 2.5 mm² (Short Circuit, Earth Conductor Withstand); 4 mm² (Short Circuit, Earth Conductor Withstand); 6 mm² (Short Circuit, Earth Conductor Withstand); 10 mm² (Short Circuit); 16 mm² (Short Circuit)
  Parallel columns assume identical cables sharing the load current, the prospective fault and the earth-fault current equally, with no grouping derating beyond the installation entered: confirm the grouping of the parallel cables separately
  The earth fault loop governs 235 of 254 usable cells
  The upstream loop impedance (0.1 Ω) alone limits the earth-fault current to 2309 A, below the disconnection current of 185 kW (2500 A): those rows have no permissible length on the earth fault loop

Recommendations:
  A larger earth conductor (earth sized as the phase), a lower disconnection multiple or an RCD lengthens the earth-fault-limited runs
  A lower disconnection multiple (an MCCB with adjustable instantaneous trip) or an RCD is needed for automatic disconnection of the largest motors

10. Standards

Cable current ratings, derating, impedances and k factors: AS/NZS 3008.1.1:2017. Disconnection by the earth fault loop, overload coordination and protective earth sizing: AS/NZS 3000:2018 (Appendix B5, Clause 2.5.3.1, Table 5.1). Preferred motor ratings per IEC 60072; preferred device ratings per AS/NZS 60898, AS/NZS 60947.2 and AS 60269.

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