HHTraff

HHTraff is a free toolkit for electrical and traffic-signal field technicians working under New Zealand and Australian wiring rules. CALCULATORS — all offline, all free • Cable Sizer — pick the smallest cable that handles the load with temperature and grouping derating applied. Common preset wiring scenarios make it fast for everyday jobs. • Voltage Drop — calculate drop using the mV/A/m method for single and three-phase circuits, with live max-length and max-load readouts so you can see how much headroom you have. • Circuit Check — verify a cable, breaker, load and length combo against AS/NZS 3000 voltage drop limits in one screen. • Earth Fault Loop — confirm Zs is low enough for the protective device to disconnect, with both measured and calculated modes. Calculations are based on AS/NZS 3000 and AS/NZS 3008 reference data. Always verify against the wiring rules that apply in your jurisdiction — HHTraff is a reference tool, not a substitute for the standards or for a qualified electrical worker. REFERENCE TOOLS — also offline, also free • Unit Converter — quick conversions for everyday field work: cable cross-section (mm² ↔ AWG ↔ kcmil), power (W, kW, HP, BTU/h), temperature (°C, °F, K), and length, area and volume in both metric and imperial units. Live two-way conversion as you type. • Cable Colours — regional wire colour reference for NZ/AU, UK, US (NEC) and EU (CENELEC) installations, plus T568A vs T568B RJ45 4-pair UTP pinouts for structured-cabling work. Read-only, no internet needed. DIAGNOSTIC TERMINAL HHTraff includes a VT100-style serial terminal for connecting to traffic-signal controllers (ATSC4, TOPAS 2500B and others) over USB or Bluetooth. Field technicians can review controller menus, capture log files to the device, and browse a built-in command quick reference for common controller families. WHO IT'S FOR • Registered electricians on residential, commercial and industrial jobs in New Zealand and Australia • Traffic-signal technicians servicing intersection cabinets • Structured-cabling and data installers needing a quick T568A/B reference on site • Apprentices learning the AS/NZS calculation methods PRIVACY HHTraff does not collect personal data, location, or analytics. See phaselogic.app/privacy for full details.