Labelling may seem like one of the least significant parts of a solar installation, but it is crucial to ensure safety and compliance, writes Clean Energy Council technical program specialist Nathan Smith.

Arguably, one of the most important elements of a safe and compliant solar and/or battery installation is the correct application of the required labelling and system documentation. Unlike the logistical challenges of lifting modules onto roofs or transporting and installing a 100kg battery pack, it is a problem of a mostly administrative nature.

However, labelling non-compliances are one of the most common defects identified by inspectors and auditors. This is perhaps because a handful of Traffolyte labels doesn’t bear the same weight as the aforementioned battery pack (pun intended) or because labelling is often left to the end of the day in the mad rush of site pack up, testing and commissioning, heat stroke, and, god forbid, fault finding.

Understanding is the first step to compliance

The best way for installers to avoid these defects is to develop a firm understanding of the relevant standards that apply to the type of installation they are conducting, with most labelling requirements being found in AS/NZS 5033 Section 5, AS/NZS 4777.1 Section 6 and AS/NZS 5139 Section 7. When read in isolation, these sections are much less daunting than looking through the entire standard, and collectively are just 14-and-a-half pages in total across all three standards.

Although there are a couple of exceptions, the labelling requirements follow the usual application of standards, with AS/NZS 4777.1 applying from the point of supply to the inverter, AS/NZS 5033 applying from the inverter to the array, and AS/NZS 5139 applying from the inverter to the battery system.

Tips for avoiding confusion

Some of the most common sources of confusion among installers when it comes to labelling arise when the installation differs from what could be considered average. This may be due to multiple switchboards or inverters onsite, outbuildings, larger or more electrically complex designs, or the addition of batteries.

While most installers tend to think of solar installations in respect to the flow of power, starting at the array and working their way back to the switchboard, it can be useful in these situations to start at the point of supply and work towards the array because this allows for evaluation of the system topology prior to its division into multiple disparate parts.

This also makes it simpler to identify when additional and/or alternative labels are required, such as for installations containing multiple main switches, inverters or switchboards, or inverters that are connected to distribution boards located remote to the main switchboard.

New standard means new labels

The publishing of AS/NZS 5033:2021 brings with it several changes to labelling requirements that installers may be familiar with. A big win for installers in these changes is the removal of the red “Fire and Emergency” information label that included the VOC and ISC of the installation. The values required for this label were not necessarily intuitive, which led to installers incorrectly filling out the label.

Changes have also been made to the familiar green “PV” label installed at the main switchboard and/or meter panel. It has increased in size from 70mm to 100mm, similar to the ES label required by AS/NZS 5139, and must now include letters to signify the type of isolation device used at the array.

New labels required by the standard include a solar system layout map or drawing located at the main switchboard, meter box or fire panel with relevant information about the solar system. Where installers elect to use disconnection points in place of load break disconnectors, as permitted by the new standard, they are required to provide labels that indicate the location of the disconnection point and that it must not be disconnected under load.

Finally, if a disconnection point is used and cabling runs in through an accessible ceiling or floor space, a sign indicating that DC cabling has been installed within must be located at the access point to this space.

Too much of a good thing

With the changes brought in by the new standard, it is also important for installers to remember that when conducting alterations or repairs/maintenance to an existing system that excessive and ancillary labelling can be just as bad as insufficient labelling.

Another problem can occur when installers rely on pre-made labelling “kits”, which can result in the important information needed to be conveyed becoming lost or contradicted when labels are installed in locations or situations where they are not required. As with the labelling of a new system, the best way to avoid this is for installers to ensure they understand the requirements of the relevant standards and select the required labels rather than relying wholly on a supplied kit having the correct type for the given system.

To support installers with the release of the new AS/NZS 5033:2021, the Clean Energy Council has developed a labelling support document reflecting the requirements of the new standard, AS/NZS 4777.1 and AS/NZS 5139. The purpose of this document is not to tell installers explicitly which labels are required for their system, but to provide advice about which labels may be required at each portion of the installation, alongside their standard and clause number.

Labelling is not only a compliance issue that is very easy for inspectors and auditors to defect installers on, but failing to have clear and accurate labelling can be a safety risk and make it difficult for emergency services, system owners or other electricians to operate the system.

Make sure you don’t get caught out – give your labelling the appropriate time and attention it deserves.