Last Updated: April 17, 2026
Quick Answer: NEC 2026 deleted Section 706.16 from Article 706, reclassifying most solar-coupled energy storage systems as optional standby power systems under Article 702. Your "ENERGY STORAGE SYSTEM DISCONNECT" label is still required per Section 706.15(C). You now also need Article 702.7(B) standby warning signage at the service equipment. Missing either label is a common reason storage-paired solar inspections fail.
If your solar+storage install just got flagged at inspection, NEC 2026 made a quiet but significant change that's catching installers off guard. The 2026 National Electrical Code deleted Section 706.16 — the provision that governed how energy storage systems connect to other power sources — and folded most ESS backup functions into Article 702 (Optional Standby Power Systems). That shift changes which labels your system needs and where they go.
This guide walks through every label required for a compliant NEC 2026 solar+storage install. The ESS disconnect label, the nameplate, the shock hazard warning, the new standby sign at your main panel — all of it, with the exact section numbers your AHJ will be checking.
Print Pro AZ handles solar+storage label sets for installers across Phoenix and nationwide. Our NEC-compliant ESS disconnect labels cover the disconnect, shock hazard, and on-site indicators you need in one order.
What Was NEC Section 706.16 and Why Was It Deleted?
Section 706.16 "Connection to Energy Sources" was removed in its entirety in NEC 2026. Under NEC 2023, Section 706.16 directed installers to size ESS backup capacity using Article 710 (Stand-Alone Systems) rules — a framework written for systems completely disconnected from the utility grid.
The problem: most residential and commercial battery storage systems aren't stand-alone. They're utility-interactive. A Powerwall or Enphase IQ Battery connected to a grid-tied solar system runs parallel with the utility all day. Article 710 sizing rules were the wrong fit for these systems, creating engineering complexity without a clear safety payoff.
The NEC 2026 technical committee eliminated Section 706.16 and redirected grid-tied ESS backup systems to Article 702 — the correct framework for systems that back up loads during utility outages but otherwise operate in parallel with the grid.
Key takeaway: The deletion of 706.16 doesn't remove any label requirements. It changes the classification framework that governs system sizing and which signage articles apply to your install.
How Does the Shift to Article 702 Change Your Label Requirements?
Article 702 (Optional Standby Power Systems) adds one labeling requirement that most ESS installs weren't carrying under the old code: a warning sign at the service equipment.
Per NEC 2026 Section 702.7(B), when an energy storage system functions as an optional standby source, a warning sign must be installed at the normal power source equipment — typically the main service panel. The sign alerts electrical workers and first responders that a standby power source is connected to the premises and identifies its location. A compliant sign reads something like:
WARNING — STANDBY POWER SOURCE ON PREMISES Energy Storage System Located at: [Location]
This sign is field-applied. It must comply with Section 110.21(B) — legible, white background, contrasting text, and durable enough to withstand the environment. That rules out hand-written paper. A UV-resistant vinyl decal or rigid plastic label is the correct choice.
What to do: When you pull your permit for a solar+storage job, confirm with your AHJ whether they want the 702.7(B) sign at the main service panel, the critical loads panel, or both. AHJ interpretation varies across Arizona jurisdictions — Maricopa County and Phoenix have different conventions for ESS signage location.
For most residential solar+storage installs, you now need:
- The existing ESS disconnect label set (Section 706.15)
- The new Article 702.7(B) standby warning sign at the main panel
Missing the 702.7(B) sign is one of the first things an NEC 2026-trained AHJ inspector will catch.
What Labels Does NEC Section 706.15 Still Require on Your ESS Disconnect?
Article 706's disconnect labeling requirements are unchanged by the deletion of 706.16. Every ESS disconnect still needs the following:
The Disconnect Identity Label (706.15(C))
Every ESS disconnect must be marked:
ENERGY STORAGE SYSTEM DISCONNECT
The disconnect must also plainly indicate whether it is in the open (off) or closed (on) position. This applies to all installation types — residential and commercial.
The Shock Hazard Warning (706.15)
If line and load terminals remain energized when the disconnect is in the open position — which is standard in battery storage systems — the disconnect must carry this warning:
WARNING — ELECTRIC SHOCK HAZARD TERMINALS ON THE LINE AND LOAD SIDES MAY BE ENERGIZED IN THE OPEN POSITION
AHJs actively look for this label. Missing it on a system with live terminals at an open disconnect is a direct code violation under Section 706.15.
The "Energy Storage System On Site" Indicator
Many AHJs require an additional "ENERGY STORAGE SYSTEM ON SITE — LOCATED WITHIN LINE OF SIGHT" label posted at an accessible exterior location. This alerts first responders and utility personnel that a battery system is present on the premises. This requirement is frequently enforced in Arizona fire jurisdictions even when not explicitly cited in the base NEC — always verify with your local AHJ before closing out a job.
Print Pro AZ carries NEC-compliant ESS disconnect labels, shock hazard warnings, and on-site indicators in UV-resistant vinyl (V-225, V-405) and rigid plastic (PV-133, PV-227). Order by product code or filter by label type.
What Does an ESS Nameplate Need to Show Under NEC 706.4?
The energy storage system itself must carry a listed nameplate showing all of the following per NEC 706.4:
- Manufacturer's name or trademark
- Rated frequency
- Number of phases (if AC output)
- Power rating in kW or kVA
- Available fault current derived from the ESS
- Maximum output and input current
- Maximum output and input voltage
- Utility-interactive capability (if applicable)
On listed equipment — a Powerwall, Enphase IQ Battery, Franklin aPower — the nameplate is factory-applied. Your job as the installer is to verify the nameplate is legible, intact, and not obscured by conduit, racking, or enclosures before the inspector arrives.
If the nameplate is missing or illegible, the AHJ will reject the installation. Per EC&M's overview of NEC Article 706 requirements, nameplate compliance under 706.4 is a common deficiency on first inspections of battery storage installations.
Are Arc Flash Labels Required on Battery Storage Systems?
For commercial and multi-family installations — yes. For residential (one- and two-family) — no, but the shock hazard warning is still required.
NEC 2026 Section 110.16 expands arc flash marking requirements and aligns with NFPA 70E-2024. For commercial ESS disconnects, the disconnect marking must include:
- Nominal battery voltage
- Available fault current derived from the ESS
- An arc flash label meeting NFPA 70E-2024 acceptable industry practice
- The date the arc flash hazard calculation was performed
Under NEC 2026, the arc flash label itself must include: system voltage, arc flash boundary, incident energy level or required PPE category, and the date of assessment. A generic "CAUTION — ARC FLASH HAZARD" decal does not satisfy this requirement on a commercial job.
Here's a scenario we see regularly at Print Pro AZ: A commercial solar installer in Phoenix called after failing inspection because the ESS disconnect carried an arc flash label printed before the 2026 update. The label was missing the incident energy level and PPE category fields. The AHJ required a replacement label with full NFPA 70E-2024 data before approving re-inspection. A five-minute label fix caused two weeks of delay on a commercial project.
For commercial storage jobs, Print Pro AZ can supply custom arc flash labels with all NFPA 70E-2024 required data fields. Send us your project details and we'll quote a compliant ESS label set for your install.
Residential vs. Commercial Solar+Storage: Label Checklist
| Label | Residential (1–2 Family) | Commercial / Multi-Family |
|---|---|---|
| "ENERGY STORAGE SYSTEM DISCONNECT" | Required | Required |
| Open/closed position indicator | Required | Required |
| Shock hazard warning (live terminals) | Required if applicable | Required if applicable |
| 702.7(B) standby warning at service panel | Required (NEC 2026) | Required (NEC 2026) |
| "ESS On Site" exterior indicator | Check your AHJ | Typically required |
| Nominal battery voltage on disconnect | Not required | Required (706.15) |
| Available fault current on disconnect | Not required | Required (706.15) |
| Arc flash label per NFPA 70E-2024 | Not required | Required (706.15 / 110.16) |
| ESS nameplate (706.4) | Factory-applied — verify legibility | Factory-applied — verify legibility |
For a complete residential solar+storage label pack, see Print Pro AZ's NEC solar bundle collections. Everything you need — disconnect labels, shock hazard warnings, on-site indicators, and rapid shutdown labels — ships in one order.
For the full breakdown of every nameplate field NEC 2026 now requires on the ESS itself — battery chemistry, voltage, and energy capacity — see our companion guide on NEC 2026 Article 706 ESS labels.
For more on all the NEC 2026 changes that affect solar installers, Mayfield Renewables has a useful technical overview of the full Article 690, 705, and 706 updates.
Frequently Asked Questions
What labels do I need for a residential solar+storage installation under NEC 2026?
At minimum: an "ENERGY STORAGE SYSTEM DISCONNECT" label at the disconnect per NEC Section 706.15(C), a shock hazard warning if terminals remain live in the open position, and a standby power source warning sign at the main service panel per Article 702.7(B). Most Arizona AHJs also require an "ENERGY STORAGE SYSTEM ON SITE" label at the exterior — confirm with your local jurisdiction before closing out the job.
Did NEC 2026 remove any label requirements from Article 706?
No. NEC 2026 deleted Section 706.16 "Connection to Energy Sources," which governed system sizing rather than labeling. All labeling requirements in Section 706.15 (disconnecting means) and Section 706.4 (nameplate) remain in effect. The deletion adds a requirement — the Article 702.7(B) standby sign — it doesn't remove any.
Does moving from Article 710 to Article 702 mean I need a transfer switch?
Not necessarily. Article 702 allows multiple compliance paths, including use of a listed Power Control System (PCS) certified to the new UL 3141 standard. A PCS can manage which loads connect when the utility drops out without a traditional transfer switch. This is a system design and engineering question — confirm which compliance path your AHJ will accept before specifying equipment.
Are paper or handwritten labels acceptable for ESS warning signs?
No. NEC Section 706.15 requires all labeling be "of sufficient durability to withstand the environment involved." Paper and handwritten labels fail this standard in virtually any outdoor or garage installation. Use UV-resistant vinyl or rigid plastic labels rated for direct-sun exposure.
Why does the 702.7(B) standby sign matter if my battery system isn't a generator?
NEC 2026's reclassification of grid-tied ESS backup systems under Article 702 (Optional Standby Power Systems) brings them under the same framework as standby generators. Section 702.7(B) exists so that utility workers and first responders know a backup energy source is on the premises and can isolate it safely. The label requirement applies regardless of whether your standby source is a diesel generator or a lithium battery system.
Conclusion
NEC 2026's deletion of Section 706.16 is one of the quieter changes in this code cycle, but it has direct consequences for your label package on every solar+storage job. The core ESS disconnect and nameplate labels from Sections 706.15 and 706.4 are unchanged. The reclassification to Article 702 adds a standby warning sign at the service panel that many installers aren't putting on their label sets yet.
Get your labels right before the inspector arrives: "ENERGY STORAGE SYSTEM DISCONNECT" at the disconnect, shock hazard warning if terminals stay live in the open position, 702.7(B) standby sign at the main panel, and arc flash labels on commercial installs per NFPA 70E-2024. Miss any of these and you're scheduling a re-inspection.
Shop NEC 2026-compliant ESS disconnect and storage labels → printproaz.com/collections/solar-electric-tags
Have a commercial storage job? Send us your plan sets and we'll put together a complete, code-compliant label set.
Questions? Call Brent: (602) 649-5305
Brent Hanke | Print Pro AZ | (602) 649-5305 | b.hanke@printproaz.com Brent Hanke is the founder of Print Pro AZ, supplying NEC-compliant labels to contractors across the country.