Full Boost Wire Sizer

Wire spec

Wire gauge 24 AWG

heavylight

0.51 Ø mm 0.205 mm²i Copper cross-section 55A/55M CSA here is copper only - from the strand build (n × strand area), excluding air gaps. Generic is straight from PowerStream. 84.2 mΩ/m

Current capacity

3.5A

24 AWG · free air

Load current

Parallel conductors i Running wires in parallel Splitting the load across several identical conductors multiplies the current capacity. Capacity is the single-wire rating × the number of conductors. Bundling auto-sets to twice the parallel count, assuming each power run has a matching ground return in the same bundle. Override below if your layout differs. Assumes equal current sharing - parallel conductors must be the same gauge, length and termination.

Bundling i Bundling & standards Heat generation is the main concern - count only adjacent current-carrying power conductors. Low-current signal and data wires don't contribute meaningful heat and are excluded. BS 7671 - the UK wiring regs. Stricter - the more conservative (safer) choice. NEC - the US code. More generous derating - allows a bit more current for the same number of bundled wires. The number of conductors is doubled by default assuming power & ground pairs (the same current will flow out and back).

Ambient temperature

Continuous load3 hrs or more - derates capacity ÷1.25

Usable capacity 3.5A

Base - free air3.5 A

Parallel ×2-

Bundling ×0.65-

Ambient ×0.82-

Continuous ÷1.25-

Voltage drop over distance

Cable run

Supply voltage

→

Load range optional

volts dropped

% of supply

volts at load

▸ Reference & method notes

Reference only. Base current capacities are PowerStream's chassis wiring figures (single copper wire in free air) from the Handbook of Electronic Tables and Formulas. Bundling applies staged grouping factors - BS 7671 Table 4C1 (bunched & enclosed) or NEC 310.15(C)(1) - on top, then ambient and continuous factors stack after that. Counts are current-carrying conductors. These are rules of thumb: motorsport looms run short and hot, and spec wire (e.g. thin-wall ETFE) is often rated well above plain copper-in-PVC, so treat the bundled figure as a conservative floor. Voltage drop uses DC resistance of solid copper. Confirm against the applicable standard and the wire manufacturer's data.

Wire spec. Selecting 55A (TE 55A0111 / M22759/32, tin-coated copper, ETFE, 150°C) or 55M (TE 55M0414, silver-plated alloy, ETFE, 200°C) swaps the resistance and outer diameter to TE Connectivity's published drawing values, which feed the volt-drop and diameter figures. TE does not publish current ratings for these wires, so current capacities are always calculated from PowerStream data regardless of the selected spec. 55A covers 8-30 AWG; 55M covers 24-30 AWG. The wire spec card shows conducting copper CSA (summed from the strand build for 55A/55M, nominal AWG for Generic) - the metal that carries current and sets resistance.

Sources: wire data from PowerStream; spec wire dimensions and resistance from TE Connectivity control drawings (55A0111, 55M0414); bundling factors from BS 7671 (IET Wiring Regulations) and NEC / NFPA 70.

Disclaimer - don't be a wounder. This tool is provided for guidance only. You are ultimately responsible for verifying every result and ensuring your design is safe, correct, and compliant with the applicable standards and regulations for your application. Full Boost Consulting Ltd accept no liability for any loss, damage, injury, or cost arising from the use of this tool or reliance on its outputs.

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DISCLAIMER:
DON'T BE A WOUNDER

FULL BOOST Wire Sizer

DISCLAIMER:DON'T BE A WOUNDER

DISCLAIMER:
DON'T BE A WOUNDER