You're right, NEC 2020 705.12(D) (formerly 705.12(B)(3) in earlier editions) and 705.13 are the key sections here. Let's break it down

The Required Labels (per NEC 2020):

You need both labels, but they serve different purposes and go in different places: Label #1 (Your "old" label)

This is the label for the backfed breaker. NEC 705.12(D) states that for backfed circuit breakers used to supply power from an interactive source, the breaker shall be marked "Line Side" as well as a permanent label that indicates the type of distributed generation system, the point of supply (in amps), and the nominal operating voltage. Placement: Directly at the backfed breaker itself. This is usually on the breaker faceplate, clearly visible. Content: Your old label is very close, but must specify the type of generation system. It should read something like this:

WARNING: SOLAR (PV) POWER SOURCE OUTPUT A: [Amps] V: [Volts](LINE SIDE)

You will need to clearly label the generation system as "SOLAR (PV)" or "ENPHASE IQ" or similiar.You can also use "PV SYSTEM" or the like, but make it obvious.(LINE SIDE) marking is required to make clear to installers that the breaker is for power entering the panel, not exiting. Label #2 (Your "new" label)

This is the maximum backfeed label for the panelboard itself. NEC 705.13 requires a permanent directory or plaque be installed at each electric service and applicable distribution equipment that specifies the location of the on-site power production source(s) and that identifies the device or equipment that isolates the on-site power production source(s) from the electric power production and distribution network. Placement: On the panelboard enclosure, typically the inside of the panel door or a clearly visible location on the outside. This should be located near the main service disconnect. Content: Your "new" label example contains the correct information as proscribed by NEC 2020 705.12(D). It needs to provide the following: The sum of the ampere ratings of overcurrent devices in circuits supplying power to the busbar, other than a main overcurrent device. The rating of the busbar. The formula used to calculate the values of the above figures.

Example Label Text

"WARNING: POWER CONTROLLED PV SYSTEM. Total Backfeed Capacity to this Panel is Limited to:[Panelboard Busbar Rating] x 1.25 - [Main Breaker Rating] = [Maximum Backfeed Amps]"

Regarding Verbiage and Color

You are correct that the NEC typically doesn't specify the exact verbiage or color of these labels. The focus is on the information conveyed. However, legibility is key. Use clear, easy-to-read fonts and durable materials suitable for the environment. A contrasting color for the text is recommended (e.g., black text on a white or yellow background).

Enphase IQ Specific Considerations

Even though the NEC doesn't call it out specifically, it's good practice to include "Enphase IQ" or "Enphase Energy System" on the panelboard label for clarity, especially if the inspector is familiar with their products. This can help quickly identify the system type during inspections or maintenance. Enphase themselves may have specific labeling requirements or recommendations in their installation manuals. Always consult the manufacturer's documentation for any additional guidance.

Summary


Backfed Breaker Label

Affix your revised "old" label (including "SOLAR (PV) Power Source Output" or similar) directly to the backfed breaker, including the "LINE SIDE" designation.2.

Panelboard Maximum Backfeed Label

Affix your "new" label to the panelboard enclosure, clearly indicating the maximum allowed backfeed current, the busbar rating, the main breaker rating, and the calculation used.3.

Legibility

Ensure both labels are permanent, legible, and easy to understand.4.

Consult Enphase Documentation: Check Enphase's installation manuals for any additional labeling requirements or recommendations specific to their IQ system.By following these guidelines, you'll be compliant with the NEC 2020 and provide clear information for installers, inspectors, and future maintenance personnel. Flag for review