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Department of Justice

Solar and Photovoltaic (PV) installations

1. Use of plastic cable ties - AS/NZS5033:2012 clause 4.3.6.3.1.

amdt. Feb 2014

Only plastic cable ties that have been manufactured and tested to have a lifespan of equal to or greater than 15 years may be used as the primary means of support, but as generally systems have a greater life expectancy than 15 years we strongly recommend the continuing use of stainless steel ties (or other suitable alternative) as the primary means of support and the additional use of 15 year cable ties to increase cable neatness. This clause applies to all cables, conduits and earth wires associated with the PV array up to the inverter that are or can be exposed to direct or reflected UV radiation.

2. Undue stress on earth connections - AS/NZS 3000:2007 Clause 3.7.2.6.

All cables and connections need to be restrained to avoid any undue stress on the connection point. This requirement includes the earth connection to all bonding points in a PV array and the connection points to the panels. Several turns of the conductor around a rail is not considered a satisfactory method. The use of suitable cable ties or similar clamping system would suffice, providing the cable ties meets the requirements of AS/NZS 5033:2012 Clause 4.3.6.3.1. (Mentioned in point 1)

3. Maintaining IP rating of enclosures - AS/NZS 5033:2012 Clause 4.4.4.5. and AS/NZS 3000:2007 clause 1.7.2.

All enclosures shall have a minimum rating of IP 54 and be selected and installed according to the environment in which they may be exposed. In order to maintain the IP rating of the enclosure adherence to the manufacturers mounting instructions is mandatory.

a) Can silicon or a similar sealant be used as a primary means of maintaining the IP rating?
No.

b) Can silicon (or similar) be used to provide a seal over the enclosure lid once the lid has been closed?
This is not recommended as resealing the enclosure after periodic opening may be problematic.

c) Do all cables need to be installed through an IP rated gland?
Yes, this includes the earth wire (unless a weather proof conduit connection is used).

d) Where can cable entries be made on the enclosure?
All cable entry’s need to be made on the side or bottom of the enclosure, cables that are installed through a side entry need to be installed with a drip loop.

e) Can multiple cables enter through one gland?
Yes, as long as an appropriate multiple cable gland is used and correctly installed to allow the internal grommet to effectively seal against the ingress of moisture.

f) Can I drill a hole to allow an earth wire to pass through the enclosure without the use of a gland?
No, all cable shall pass through an IP rated gland, or appropriate weatherproof conduit connection.

4. Isolators mounted on side of PV panels - AS/NZS 5033:2012 Clause 4.4.1.4.

Isolators shall not be mounted directly to the side of solar panels. This interpretation is intended to allow a panel to be removed and replaced without the need to disconnect or remove the isolator and secondly intended to prevent holes being drilled into the side of the panel frame. Isolators need to be mounted via a bracket to the array frame or similar.

5. Minimum size a.c. cable - AS 4777.1 Clause 5.3.2. and AS/NZS 3000:2007 clause 3.4.1.

The current carrying capacity of all cables shall be selected and installed to accommodate full load of all PV panels in the system.

Particular attention must be given to existing sub mains cables installed between main switchboards and other sub distribution boards when the array is connected to the sub board.

6. Marking of PV array wiring and associated enclosures - AS/NZS 5033:2012 Clause 5.3.1.

Conduit and other wiring enclosures.
These shall be marked with the word ‘SOLAR’ at each end of the enclosure and at each change in direction.

Cabling
PV cables shall be permanently marked every 2 meters with the words SOLAR. The marking shall be in English, indelible, legible and be in a distinctive colour.

7. Documentation to be supplied to system owner - AS/NZS 5033:2012 Clause 5.7.

It is a mandatory requirement of this standard that all the documents listed in Clause 5.7 be provided to the owner of the installation, this is best achieved by compiling a manual or folder.

This requirement is in addition to the “Record of Electrical Work” copy required to be issued to the customer by the Occupational Licensing (Electrical Work) Regulations 2009.

8. Earthing of PV panels and mounting rails - AS/NZS 5033:2012 Clause 4.4.2.

This requirement is best split into two areas:

Metal frames of Photovoltaic panels

If the array open circuit voltage is above extra low voltage then all module metal frames need to be earthed irrespective of the location, inverter or installation method

Mounting rails or frames

If the solar panel metal frames need to be earthed due to the array voltage being above extra low voltage and all array cabling is not fully enclosed in conduit or ducting then the rails and mounting frames also need to be earthed.

All earthing shall be performed with consideration to the following:

a) No stress on the earthing connection, see requirements of AS/NZS 3000:2007 Clause 3.7.2.6.

b) Size selected from table 5.1 in AS/NZS 3000:2007, However be aware that AS/NZS 5033:2012 fig 4.3 requires a minimum size of 4mm2

9. Alterations and Additions to existing PV Arrays - AS/NZS 3000:2007 Clause 1.9.3.

What alterations or additions to existing solar generation systems require the original installation to be brought up to date with the current standard?

a) Adding panels to an existing array (e.g. original array had 6 panels in series, the upgrade is adding 2 new panels in series with the existing)

i. All panels and mounting structure would need to be earthed.

ii. No Plastic cable ties used on the new panels or associated wiring (unless supplementary for neatness).

iii. A roof top isolator needs to be fitted. If the isolator is existing, it needs to be suitably rated and capable of handling the additional voltage and current.

iv. The inverter limitations must not be exceeded by the additional panels.

v. If the PV array cable is still within the voltage and current rating and does not require replacement, it does not need to be enclosed in HD conduit, provided it met the standard of the day.

vi. Approval for the additional generation capacity shall be obtained from the network service provider, prior to commissioning of additional panels.

b) Adding panels to an existing string but changing the configuration of the existing string (e.g. original there was 10 panels in series; 2 panels are added but the configuration of the array is to be in 2 strings of 6)

i. All panels need to be earthed.

ii. No Plastic cable ties used on the new panels or associated wiring (unless supplementary for neatness).

iii. A roof top isolator needs to be fitted. If the isolator is existing, it needs to be suitably rated and capable of handling the additional voltage and current.

iv. The inverter limitations must not be exceeded by the change in configuration and additional panels.

v. If the PV array cable is still within the voltage and current rating and does not require replacement, it does not need to be in HD conduit, provided it met the standard of the day.

vi. Approval for the additional generation capacity shall be obtained from the network service provider, prior to commissioning of additional panels.

c) Adding a new string to an existing string paralleling on the roof.

i. All panels need to be earthed.

ii. No Plastic cable ties used on these new panels or associated wiring (unless supplementary for neatness).

iii. A rooftop isolator needs to be fitted. If the isolator is existing, it needs to be capable of handling the additional voltage and current.

iv. The inverter limitations must not be exceeded by the additional panels.

v. If the PV array cable is still within the voltage and current rating and does not require replacement, it does not need to be in HD conduit, provided it met the standard of the day.

vi. Approval for the additional generation capacity shall be obtained from the network service provider prior to commissioning of additional panels.

d) Adding a new string to an existing string, paralleling the circuits at the inverter.

i. All panels need to be earthed.

ii. No plastic cable ties used on these new panels or associated wiring (unless supplementary for neatness).

iii. A roof top isolator needs to be fitted. If the isolator is existing, it needs to be capable of handling the additional voltage and current.

iv. The inverter limitations must not be exceeded by the additional panels.

v. If the PV array cable is still within the voltage and current rating and does not require replacement, it does not need to be in HD conduit, provided it met the standard of the day.

vi. Approval for the additional generation capacity shall be obtained from the network service provider prior to commissioning of additional panels.

e) Inverter replacement

Same type: (e.g. a transformer inverter is replaced with a transformer inverter)
If the type (topology) of the inverter is not changed then it is a direct, like for like, replacement.
Remember the following:

a) AS / NZS 3000;2007 clause 1.7.2. (b) (manufacturers requirements) that may require additional or different installation requirements.

b) Any additional requirements or regulations pertaining specifically to the new type (topology) of inverter shall apply; this shall include the existing array and associated cabling.

Different Type: (e.g. a transformer inverter is replaced with a transformer less inverter)
If the type (topology) of the inverter is changed then it is not a direct, like for like, replacement:

a) All requirements regarding manufactures instructions would need to be adhered too.

b) It is a recommendation that a roof top Isolator is installed in the case where one does not exist.

f) Panel replacements

Scenario 1
In this scenario the system has been installed and is connected to the grid. The customer wants the panels removed for the roof to be replaced or repaired and on completion of the repairs the panels re-installed in the same location.

Answer 1
This is no different to a house being demolished and a salvage team removes wiring etc. When this electrical equipment is reinstalled it must comply with the ruling standard enforced at the time of the refit. This is treated as a new installation.

Scenario 2
The system has been installed and is connected to the grid. The customer wants the panels removed for and extension to be built and then the panels re-installed on the new extension.

Answer 2
As per answer 1

Scenario 3
If a higher wattage panel is used to replace a faulty panel simply because the old panels are no longer commercially available, e.g.175W panel is faulty, replaced with a 180W of the same make and series. Does just that one panel have to be installed to the new standard (earthed, cable ties as per AS/NZS5033:2012)? Is a roof top isolator required to be installed?

Answer 3
Replacement of a faulty or damaged module would require that the particular replaced module be installed as per the requirements of the current standard, this replacement would not invoke any changes or upgrades to the rest of the installation, unless the new module has a higher power rating that exceeds any previous limitations. A roof top isolator would not need to be installed.

10. PV d.c array cables within buildings - AS/NZS 5033:2012 Clause 4.3.6.3.2.

PV wiring that is installed under a roofed porch, veranda, portico or similar structure is deemed to be within a building and therefore required to be installed within insulating heavy duty conduit.

11. Labelling of Main Switchs and Isolators - AS/NZS4777.1:2005 & AS/NZS3000:2007

Information regarding the identification of main supplies and isolators, in switchboards, by marking or labeling.