Solar labeling exists so that somebody who did not install the system can understand it in a hurry, which usually means an inspector at sign-off or a firefighter on a roof at night. That is why the requirements are specific about wording, durability, and placement rather than leaving it to whoever holds the label printer. The catch is that requirements depend on which edition of the code your jurisdiction has adopted, and that varies. Our guide to grounding requirements covers another area where local rules decide the answer.
A Note on Code
This is general information about label types, not a compliance guide. Which labels you need depends on your adopted NEC edition, local amendments, and your authority having jurisdiction. Confirm requirements with your AHJ or plans examiner before ordering anything, since a full set of labels for the wrong code cycle is wasted money.
Label Types at a Glance
| Label | Goes on | Typical format | Purpose |
|---|---|---|---|
| Rapid shutdown building placard | Service equipment | Contrasting text, roof graphic | Tells responders RSD exists |
| RSD initiation device label | At or near the switch | Red, white text, reflective | Identifies the switch itself |
| PV power source markings | Conduit, boxes, enclosures | Durable, permanently affixed | Warns of energized DC |
| DC electrical data label | DC disconnect | Voltage and current values | System electrical parameters |
| Power source directory | Service equipment | Plaque or directory | Identifies all sources on site |
| Disconnect identification | Every disconnect | Clear text | Says what it isolates |
The short version: buy UL 969 rated label stock rather than printer paper and laminate, since durability is an actual code requirement rather than a quality preference. Then confirm the wording against your adopted code edition before ordering a full set.
How We Picked
Labels are grouped by what they identify and where they mount, since placement and wording are what an inspector checks. Material durability is weighted heavily throughout, because a label that fades or peels within a few seasons fails the requirement that field markings be permanent.
Selection criteria reflect material specifications, adhesive type, and format. Descriptions come from published code guidance and product documentation rather than from installations we have submitted for inspection.
1. A UL 969 Rated Label Set, Best Overall
Why It Stands Out
Pre-printed sets on UL 969 rated polyester or polycarbonate cover the standard label positions in one purchase, with materials made for outdoor exposure and adhesives intended to stay put.
NEC 110.21(B) requires field-applied hazard markings to be durable enough for the environment, which is the specification a home printer and a laminating pouch will not meet after a couple of summers.
Worth Knowing
Sets are sold by code cycle, and the wording differs between editions. The 2023 NEC moved the rapid shutdown building placard requirements from 690.56(C) into 690.12(D), so a set printed for one cycle may not match what your inspector is reading from.
Check which edition your jurisdiction has adopted before ordering. Local amendments sit outside the base code and are easy to miss. Our roundup of disconnect switches covers the equipment several of these labels attach to.
This suits most residential installs. Skip it if your AHJ supplies its own templates.
2. A Rapid Shutdown Switch Label, Best Single Requirement
Why It Stands Out
The label identifying the rapid shutdown initiation device is one of the more consistent requirements across code cycles, and its format has not changed the way the building placard has. Red background, white lettering, reflective, all capitals, with a minimum letter height.
It also has to be at or very near the switch itself, so a responder finding the placard at the service equipment can then find the actual device.
Worth Knowing
Reflectivity matters here in a way it does not on every label, because the intended reader may be looking at it with a flashlight at night.
The building placard at the service equipment and the label at the switch are two different labels doing two different jobs. Fitting one and not the other is a common gap. Our note on fuses and breakers covers other equipment inspectors examine closely.
This suits any system with rapid shutdown. Skip it only if your system genuinely has none.
3. Photovoltaic Power Source Conduit Markings, Best for Runs
Why It Stands Out
Conduit, raceways, junction boxes, and enclosures carrying PV DC conductors need marking so nobody opens one assuming it is dead. These labels are what stop a technician treating an energized DC run as ordinary wiring.
They also need to remain visible after installation, which means marking the exposed face rather than a surface that ends up against a wall.
Worth Knowing
Marking intervals along a run can be specified by the fire code rather than the electrical code, and those requirements are separate from the NEC. This is another point where the AHJ decides.
Adhesive labels on conduit need a clean dry surface and fail on dusty or oily pipe. Our roundup of wire management and conduit covers the runs these mark.
This suits any system with exposed DC conduit. Skip it where all DC is inside the array.
4. A DC Electrical Data Placard, Best for the Disconnect
Why It Stands Out
A placard listing the system’s DC electrical parameters lets an inspector verify the installation matches the plan set without tracing the whole system.
These are generally write-on or custom-printed, since the values are specific to your array rather than standard text.
Worth Knowing
The 2023 NEC relocated the DC voltage marking requirement from 690.53 to 690.7(D), so the reference an older label set cites may not match a current plan review.
Values have to be correct for the system as built rather than as originally designed, so fill these in at the end. Our note on sizing solar wire covers the figures involved. Our note on winterize a solar system covers that in more detail.
This suits any permitted installation. Skip it for a genuinely off-grid unpermitted system, while checking that assumption carefully.
5. A Power Source Directory Plaque, Best for Multi-Source Sites
Why It Stands Out
Where a property has solar, storage, or a generator alongside the utility supply, a directory at the service equipment identifies every source in one place. The 2023 NEC consolidated these premises-level identification requirements into Article 705.10.
For anyone arriving to work on the building, that single plaque answers the question of what else could be energizing the system.
Worth Knowing
This is a site-level label rather than an equipment label, so it needs updating if you later add batteries or a generator. An outdated directory is arguably worse than none.
Format expectations vary between jurisdictions, and some AHJs have a preferred template. Our roundup of battery enclosures covers equipment that would need adding to one.
This suits sites with more than one source. Skip it for a simple grid-tied array with nothing else.
6. A Blank Label Printer and Stock, Best for Custom Text
Why It Stands Out
An industrial label printer with rated stock produces custom wording on demand, which suits anyone doing several systems or working under an AHJ with specific requirements.
It also handles disconnect identification, where every switch needs text describing what it actually isolates rather than generic wording.
Worth Knowing
The printer is only as compliant as the stock. Ordinary label tape is not rated for outdoor exposure, and using it defeats the purpose of buying the machine.
For a single home system this is more equipment than the job needs, and a pre-printed set costs far less. Our guide to combiner boxes covers other enclosures needing identification.
This suits installers and multiple systems. Skip it for one array.
How to Choose Solar Labels
Which code edition applies?
This decides the wording. Jurisdictions adopt NEC editions on their own timetable, and a design correct under one cycle can be redlined under another. Ask the plans examiner before ordering.
Is the material rated?
Field-applied hazard markings must be durable for the environment. UL 969 rated polyester or polycarbonate with outdoor-grade inks is what meets that; a laminated printout does not.
Where does each one go?
Placement is checked as carefully as wording. The building placard goes at the service equipment, the switch label goes at the switch, and conduit markings must stay visible after installation.
Does your AHJ have templates?
Many do, and using them removes the guesswork entirely. This single question saves more trouble than any product choice in this category.
Pre-Printed or Custom?
The case for pre-printed sets
Correct wording, rated materials, and everything in one purchase. For a single residential system this is the straightforward answer, provided the set matches your code cycle.
The case for printing your own
Disconnect identification and system-specific data need custom text, and an AHJ with particular preferences may not be served by a generic set. The requirement is rated stock rather than ordinary tape. Our roundup of grounding equipment covers another area inspectors examine in detail.
Common Labeling Mistakes to Avoid
Buying for the wrong code cycle
Requirements moved between the 2020 and 2023 editions, including where the rapid shutdown placard requirements live and what format they specify. Confirm the adopted edition first.
Using paper and laminate
Field markings have to be durable and permanently affixed. A laminated printout fades and peels, and an inspector who has seen it before will recognize it immediately.
Labeling the placard and not the switch
These are two separate requirements. The building placard says rapid shutdown exists; the switch label says this is the device. Both are needed.
Placing labels where they end up hidden
Markings must remain visible after installation, so a label on the back of a box that faces a wall does not count. Think about the finished installation rather than the moment of application. Our note on mounting kits covers planning the finished layout.
Worth reading next: our junction box picks, notes on MC4 tools, our busbar roundup, and a guide to install tools.
Solar Labeling FAQ
What labels does a solar system actually need?
Typically a rapid shutdown placard at the service equipment, a label at the shutdown switch itself, PV power source markings on DC conduit and enclosures, electrical data at the DC disconnect, and identification on every disconnect. The exact set depends on your adopted code edition and your AHJ.
Can I print my own solar labels?
Only on materials rated for the environment. Field-applied hazard markings must be durable and permanently affixed, which ordinary paper and laminate do not achieve. UL 969 rated stock with outdoor-grade ink is what meets the requirement.
Did the labeling requirements change in the 2023 NEC?
Several did. The rapid shutdown building placard requirements moved from 690.56(C) to 690.12(D), the DC voltage marking moved from 690.53 to 690.7(D), and premises-level power source identification consolidated into 705.10. Whether those apply to you depends on which edition your jurisdiction has adopted.
Do the labels have to be red?
The label at the rapid shutdown initiation device is conventionally red with white lettering and reflective. The building placard requirements changed between code cycles regarding color, so check what your adopted edition specifies rather than assuming red is always required.
Where does the rapid shutdown placard go?
At or adjacent to the service equipment, plainly visible, so a responder arriving at the property finds it without searching. The separate label identifying the initiation device goes at or very near the switch itself.
Does an off-grid system need labels?
If it is permitted and inspected, yes, and the requirements are similar. Even where inspection is not involved, marking DC conduit and disconnects is worth doing for anyone who works on the system later, including you in five years.
How long do solar labels last?
Rated polyester and polycarbonate labels are made to survive years of outdoor exposure, which is the point of the specification. Cheaper vinyl and printed paper fade and peel within a season or two, and a faded label is a failed one.
Who decides what I need?
Your authority having jurisdiction. They determine which code edition applies, whether local amendments add requirements, and sometimes provide templates. Asking the plans examiner before ordering is the single most useful step in this whole process.
For the wider picture, see our guide to how to choose a solar battery.
