EV चार्जर सर्किट कैलकुलेटर

How this is calculated#

The tool checks an EV charger circuit. It reads Clause 7.9.3.3 of AS/NZS 3000:2018 for the circuit, the RCD and the isolating switch. It reads Table C1 for the charger demand. It then takes a cable size from the cable size calculator.

1. Circuit rules. The tool prints the minimum final subcircuit capacity and the other points allowed on it. It also prints the isolating switch rating (Cl 7.9.3.3).
2. RCD. It prints the maximum rated residual current, the type and the arrangement of the device. It also lists the Exception that allows a device with RDC-DD.
3. Charger demand. It counts the chargers on the heaviest phase. It applies the share of rated current that group (j)(iv) of Table C1 counts. Load management can set a lower limit.
4. Spare capacity. It subtracts your maximum demand from the supply rating. It then subtracts the charger demand.
5. Cable. It takes the design current for the charger. It sizes the cable and gives the drop over your run.

Worked example#

• 32 A Mode 3 charger on a 63 A supply with a 40 A demand. The charger is 20 m from the board. The tool finds the board short by 9 A. It gives a 6 mm² cable with a 2.09 % drop.

Limits#

• The tool reads the clause and prints its figures. It is a pointer to the clause, not a ruling on a design.
• Clause 7.9 adds to Sections 2 to 7. A figure the tool does not report can still come from those Sections.
• The clause prints a capacity figure for single‑phase circuits only. It prints none for a three‑phase circuit.
• The RDC-DD level comes from a NOTE. A NOTE is not a requirement.
• The cable uses the default inputs of the cable size tool. Open that tool to set grouping or ambient.
• The tool reads the 2018 edition with Amendments 1, 2 and 3. It does not read the supply authority rules.
• The install record lists what to check and keep, with each source. You tick the rows. The tool judges none of them.

See also: Clause 7.9 and EV charging in NZ, EV charging load and spare capacity and EV charger spare capacity on a 63 A main switch.