Cable Volt Drop Table

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System voltage *

Cable insulation

Copper multicore cables. V_c is read from AS/NZS 3008.1.1:2017 Table 42 at the insulation's rated conductor temperature (a fully loaded cable).

Number of parallel cables

Max running voltage drop *

Standard AS3008 limit is 5%

Max display cable length

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Calculation No.: Calc-001
Revision: A
Description:
Created By: Engineer Name

Project: Project Name
Project No.: P001
Client: Client Name

Maximum cable length reference matrix based on running voltage drop per AS/NZS 3008.1.1:2017.

1. Input Parameters

System parameters for voltage drop matrix:

Parameter	Symbol	Value	Notes
Cable Insulation		XLPE (X-90)	Rated conductor temperature 90 °C selects the Vc column
System Voltage	V	415 V	Line-to-line voltage
Max Voltage Drop	Vd%	5 %	Running voltage drop limit
Parallel Cables	P	1	0.9 derating if > 1
Max Display Length	L_max	10 km	Display cap for matrix

2. Voltage Drop Formula

Maximum cable length for a given motor and cable combination: Where: L = max cable length (m), Vd% = voltage drop as decimal, V = system voltage (V), P = parallel cables, I = full load current at V (A) = I_415 × 415 / V, Vc = three-phase voltage drop factor (mV/A.m), AS/NZS 3008.1.1:2017 Table 42 Column 8 (Cu multicore circular, 90 °C, maximum value)

Formula: $$ \begin{aligned} L &= \frac{V_{d\%} \times V \times 1000 \times P}{I \times V_c} \\ &= \frac{0.05 \times 415 \times 1000 \times 1}{I \times V_c} \end{aligned} $$

3. Cable Data Reference (Cu Multicore, 3-Phase)

Voltage drop factors from AS/NZS 3008.1.1:2017 Table 42 Column 8 (Cu multicore circular, 90 °C, maximum value) and the indicative derated current ratings:

Parameter	Symbol	Value	Notes
2.5 mm²	Vc	16.4 mV/A.m	CCC: 33 A
4 mm²	Vc	10.2 mV/A.m	CCC: 44 A
6 mm²	Vc	6.8 mV/A.m	CCC: 56 A
10 mm²	Vc	4.05 mV/A.m	CCC: 74 A
16 mm²	Vc	2.55 mV/A.m	CCC: 98 A
25 mm²	Vc	1.61 mV/A.m	CCC: 131 A
35 mm²	Vc	1.17 mV/A.m	CCC: 162 A
50 mm²	Vc	868 mmV/A.m	CCC: 197 A
70 mm²	Vc	609 mmV/A.m	CCC: 251 A
95 mm²	Vc	450 mmV/A.m	CCC: 302 A
120 mm²	Vc	366 mmV/A.m	CCC: 349 A
150 mm²	Vc	307 mmV/A.m	CCC: 393 A
185 mm²	Vc	259 mmV/A.m	CCC: 454 A
240 mm²	Vc	216 mmV/A.m	CCC: 532 A
300 mm²	Vc	190 mmV/A.m	CCC: 601 A
400 mm²	Vc	171 mmV/A.m	CCC: 686 A
500 mm²	Vc	158 mmV/A.m	CCC: 780 A

4. Summary Statistics

Total combinations: 578
Valid combinations: 282
N/A (cable undersized): 224
Exceeds max display: 72

5. Notes

- Vc per AS/NZS 3008.1.1:2017 Table 42 Column 8 (Cu multicore circular, 90 °C, maximum value): every cable is taken at the 90 °C rated temperature of XLPE (X-90) insulation (fully loaded)
- Current screen uses the component's indicative derated ratings (one fixed installation condition)
- 0.9 parallel derating factor applied when cables > 1
- Running voltage drop only (not startup)
- Motor FLC values are tabulated at 415 V, 3-phase, and scaled by 415 / V to the system voltage
- Full 34×17 matrix available in interactive view

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