Getting the solar labelling requirements right is the difference between a clean inspection and a return trip to site. A rooftop solar and battery install in Australia needs a surprising number of labels — DC isolator labels, warning signs, ID tags and reflective discs — and each one has a size, a colour and a place it has to go. This is the complete practical checklist, split into the PV side and the battery side, with the sizing and colour rules pulled straight from the standards.
The labels come from four standards working together: AS/NZS 5033:2021 (PV arrays), AS/NZS 5139:2019 (batteries), AS/NZS 4777.1:2024 (inverters) and AS/NZS 3000:2018 (the Wiring Rules). The Clean Energy Council's Advice on Labelling (Version 2, June 2023) pulls them into one place. If you want the STC photo-evidence side of this, see our separate guide on CER photo rules for solar labelling.
The general sizing rule
Before the specific labels, the baseline. The CEC sizing rule is 5mm uppercase / 4mm lowercase per metre of viewing distance, unless a particular label specifies its own minimum. Several do, and those minimums override the general rule. Get a torch out and stand where a person would actually read the label — that distance sets your letter height.
PV side — the label checklist
These come mostly from AS/NZS 5033, with the main-switch wording from AS/NZS 4777.1. Work through them as a checklist on every PV job:
| Label | Minimum size / placement |
|---|---|
| WARNING — HAZARDOUS d.c. VOLTAGE | Minimum 10mm letters |
| WARNING — PV STRING DISCONNECTION POINT | Minimum 10mm letters, within 300mm of the disconnection point |
| Cable warning — "WARNING — LOADS MUST BE ISOLATED AND CIRCUIT MUST BE TESTED FOR THE ABSENCE OF CURRENT BEFORE UNPLUGGING" | Within 100mm of the disconnection point, on the + and − cables |
| PV ARRAY d.c. ISOLATOR | Identifies the DC isolator |
| WARNING — MULTIPLE d.c. SOURCES. TURN OFF ALL d.c. ISOLATORS TO ISOLATE EQUIPMENT | Where there is more than one DC isolator |
| Green "PV" sign (retro-reflective) | Circular, minimum 100mm diameter, at/adjacent to the main metering panel and main switchboard |
The 2021 change you can't ignore: "disconnection point" and the DP sub-letter
The green retro-reflective "PV" disc isn't just a disc any more. Since AS/NZS 5033:2021 there's a sub-letter below the "PV" that tells emergency personnel how the array is isolated:
- AC — micro-inverter or AC module system
- DP — disconnection point
- SW — switch-isolator
The 2021 edition moved away from a mandatory rooftop DC isolator toward a "disconnection point" — which is why you now see DP signage. A load-break isolator is still required at or near the inverter; the change is about what sits on the roof, not about deleting the isolator at the inverter end.
Main switch wording — use the current AS/NZS 4777.1:2024 terms
AS/NZS 4777.1:2024 is the current edition and it standardised the main-switch wording. Use these:
- MAIN SWITCH (INVERTER SUPPLY)
- MAIN SWITCH (GRID SUPPLY)
- MAIN SWITCH (BATTERY) — where applicable
The legacy phrase "MAIN SWITCH SOLAR SUPPLY" is out of date. If your label stock still says that, retire it. The multiple-supply warnings also belong to 4777.1: "WARNING — MULTIPLE SUPPLIES. ISOLATE INVERTER SUPPLY AT [location]", and on the board directly connected to the inverter energy system, "WARNING — MULTIPLE SUPPLIES. ISOLATE ALL SUPPLIES BEFORE WORKING ON THIS SWITCHBOARD". Treat the exact casing as indicative and confirm against the current edition.
Battery side — the label checklist
Add a battery and AS/NZS 5139 brings its own set. Work through these:
| Label | Minimum size / placement |
|---|---|
| Green "ES" sign (retro-reflective) with the UN number for the cell chemistry below it (e.g. UN3480 for lithium / LiFePO4) | Minimum 100mm diameter, at the main meter panel and main switchboard |
| DANGER — RISK OF BATTERY EXPLOSION. NO SMOKING, SPARKS, FLAMES | At least 175mm × 175mm, at the enclosure or room doors |
| BATTERY SYSTEM ID label | With short-circuit current and maximum DC voltage |
| BATTERY SYSTEM D.C. ISOLATOR | Identifies the battery DC isolator |
| BATTERY cable marking | On battery cabling, every 2m |
| Shutdown procedure | Site-specific, adjacent to the inverter / PCE |
| WARNING — ARC FLASH HAZARD | Where the assessed arc-flash risk is above minor |
That last one matters more than it looks. AS/NZS 5139 is one of the few Australian standards that explicitly calls for an arc-flash warning, and the trigger is a risk assessment, not a guess. If you're not sure how to source the values that go on a full arc-flash label, we've written that up separately — see our arc flash warning labels guide.
Colours that pass inspection
The CEC colour conventions are not optional decoration — an inspector reads colour before they read text. Get these right:
| Purpose | Colour |
|---|---|
| General information | White background, black text |
| Essential safety | Yellow background, black text (5033 also requires a warning symbol) |
| Emergency personnel | Red background, white text |
| PPE (per AS/NZS 5139) | Blue background, white text |
| Special PV / ES signs | Green retro-reflective |
Why engraved labels are the safe choice here
This is the part most installers don't know. The CEC says labels in direct sunlight must be UV resistant and pass IEC 60068-2-5:2018 — a 720-hour carbon-arc UV chamber test. A lot of printed labels won't pass it. But Appendix A carries an exception:
This requirement does not apply to markings that are physically engraved, embossed or etched with durable markings.
Engraved labels are exempt from the UV chamber test, because there's no ink to fade. With engraved traffolyte the mark is cut into the material — the colour core is exposed, so the legend can't fade, peel or smudge. That makes the "indelible" requirement automatic, and you don't have to chase test reports from a supplier.
Be honest about the limit, though. The engraved legend won't fade, but the plastic substrate can chalk or yellow under years of direct sun. For long-term outdoor or coastal exposure, ask for a UV-stabilised grade or step up to metal. The standard doesn't care about cosmetics — it cares that the marking stays legible — but you want the tag to still look right in year fifteen.
The one thing engraved labels don't replace
The green "PV" and "ES" discs must be retro-reflective — they have to bounce a torch beam back in a dark roof void or meter cavity. That's a different material from engraved traffolyte, and engraving doesn't substitute for it. Source the reflective discs separately and engrave everything else.
Designing your solar labels
Our online label designer includes a Solar PV tag template (100mm circle) and presets for the AS/NZS sizing and colour conventions, so you're not eyeballing letter heights against the viewing-distance rule. Pick the tag, set the wording, and the price is instant. For the full kit — switchboard tags, cable markers, isolator labels and the rest — see our electrical labels range. Everything is laser-engraved in Townsville with 1–3 business day production and no minimum order.
References
- AS/NZS 5033:2021 — Installation and safety requirements for photovoltaic (PV) arrays
- AS/NZS 5139:2019 — Electrical installations: Safety of battery systems for use with power conversion equipment
- AS/NZS 4777.1:2024 — Grid connection of energy systems via inverters: Installation requirements
- AS/NZS 3000:2018 — Electrical installations (Wiring Rules)
- Clean Energy Council — Advice on Labelling (Version 2, June 2023)
- IEC 60068-2-5:2018 — Environmental testing: Simulated solar radiation at ground level
This article summarises publicly available guidance and is not a substitute for advice from a licensed electrician or accredited installer, or from your inspector. Confirm the specifics against the current edition of each standard and your network service provider's requirements before you rely on it.