AS/NZS 5033:2021
The standard for installing PV arrays. The PV string tool reads its voltage correction, its voltage limits and its string current figures. The PV array tool reads its isolator, enclosure and earthing figures and its earth fault interrupter table. All are verified on the printed pages.
Notes
- Edition cited
- AS/NZS 5033:2021
- Amendments applied
- No amendment named in the source (4 tables)
- Tables last checked
- 1 Oct 2026
- Tables
- 4: 4 verified
- Clauses
- 20
No text of the standard is reproduced here. AmpSize is a design aid. Verify results against the current standard.
Contents (24)
Clauses (20)
Maximum voltage of PV d.c. circuits
The PV string tool holds the string voltage at the coldest cell to 1000 V domestic and 1500 V elsewhere.
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Maximum string current
The PV string tool takes 1.25 times KI times the module Isc as the maximum string current.
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Fault current from parallel strings
The PV string and PV array tools compute the fault current the other strings can feed into one string. They multiply the string current by the number of strings less one.
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PV string calculator and PV isolator and earthing calculator.
When strings take overcurrent protection
The PV string tool compares the parallel-string fault current and the backfeed with the module’s fuse rating.
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Earth fault alarm
The PV array tool calls for an earth fault alarm above 120 V or with a non-separated inverter.
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PV module maximum voltage
The PV string tool corrects Voc to the record low with the maker’s coefficient, or with Table 4.1.
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String voltage limit
The PV string tool finds the most modules a string can hold. It keeps the cold string voltage at or below the limit this clause sets.
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PV isolator voltage rating
The PV array tool reports the least voltage rating of the isolator: the maximum voltage of the array.
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Ratings of a PV d.c. switch-disconnector
The PV array tool gives the least Ithe at the operating ambient, the least Ie and the least make and break current, by Table 4.3 or Table 4.4 for the inverter type.
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PV cable temperature
The PV tools take the cable temperature near the modules as the record high plus 40 K. You size each cable at that temperature.
Tools that read it:
PV string calculator and PV isolator and earthing calculator.
Smallest PV conductor
The PV string tool reports the smallest conductor size a PV cable may use, from this clause.
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PV voltage drop
The PV string tool states the voltage drop limit for an array above 120 V. It measures from the furthest module to the inverter.
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Outdoor enclosure pressure equalization
The PV array tool reminds you to fit a pressure equalization valve to an outdoor enclosure. A gland or drain near it also serves.
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Frame earth resistance
The PV array tool states the resistance limit from the array frames to the installation earth, from this clause.
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Frame earthing conductor
The PV array tool reads the least earth conductor size for the frames from this figure. That size is for mechanical strength.
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String overcurrent protection rating
The PV string tool finds the window for a string fuse rating from this table. The rating sits above the string current factor and at or below the module rating.
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Current in PV circuits
The PV string tool reads the string and array circuit currents here, with no sub-array or array protection.
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Switch disconnector ratings
The PV string tool rates the d.c. isolator for the whole array current at the string voltage.
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Enclosures for PV disconnection devices
The PV array tool names the enclosure standard for the device and the enclosure type, and the least IP code outdoors.
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PV array earth conductor size
The PV array tool follows Figure 4.13 to a column of this table, and reads the AS/NZS 3000 columns through Table 5.1.
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Tables (4)
PV array voltage, current and cable limits
The PV string tool reads the voltage limits, the 1.25 string current factor, the string fuse multiplier, the 4 mm² conductor and the 5 % drop here. Verified on the printed pages.
Verified: read against the printed standard, pages 21, 23, 24, 49, 50 (PDF 29, 31, 32, 57, 58). Checked 1 Oct 2026.
Tools that read it:
PV string calculator and PV isolator and earthing calculator.
PV array isolator, enclosure and earthing figures
The PV array tool reads the isolator ambient temperatures, the outdoor IP codes, the earthing sizes of Figure 4.13, the 0.5 ohm limit and the 120 V alarm threshold here.
Verified: read against the printed standard, pages 26, 37-39, 55, 65-67 (PDF 34, 45-47, 63, 73-75). Checked 1 Oct 2026.
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Nominal overcurrent rating of earth fault interrupter
The PV array tool reads the earth fault interrupter setting for the total array power, where the array has direct functional earthing.
Verified: read against the printed standard, pages 26 (PDF 34). Checked 1 Oct 2026.
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Voltage correction factors for crystalline silicon PV modules
The PV string tool reads the voltage correction factor for the record low when you pick the table method. Verified on printed page 29.
Verified: read against the printed standard, pages 29 (PDF 37). Checked 1 Oct 2026.
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