March 9, 2023

Enphase IEEE 1547-2018 compliance update

DIY solar

IEEE 1547-2018 latest updates

  • The following Enphase products are now certified as IEEE 1547-2018 compliant by Underwriters Laboratories: IQ8 Microinverters, IQ7 Microinverters, IQ Battery 3/3T/10/10T (as IQ8X-BAT Microinverters) and IQ System Controller 1/2.
  • IQ8, IQ8X-BAT and IQ7 Microinverters, as well as IQ Battery 3/3T/10/10T, are now also listed with HECO (HI) as SRD 2.0 compliant.
  • IQ8, IQ8X-BAT and IQ7 Microinverters, as well as IQ Battery 3/3T/10/10T, are listed with CEC as UL1741 SB and SA compliant.
  • States that have adopted IEEE 1547-2018: New York, Pennsylvania (PPL), New England states (MA, CN, RI, NH, VT, ME) as of Jan 1, 2023; Hawaii as of Feb 1, 2023.
  • California and New Mexico are the next states to implement IEEE 1547:2018 starting on April 1, 2023.

We are proud to announce that our industry-leading Enphase IQ8 Microinverter system is the first home energy system in the world that is built to the rigorous new standards to connect to the grid in North America. These necessary improvements to how distributed energy resources (DERs) communicate with utilities are critical and enable our products to adapt more efficiently and cost effectively to the ever-evolving conditions of the grid.  

Throughout our close working relationship with UL over the years, we've partnered in the development of standards for products everywhere and have now been able to quickly reach compliance with UL 1741 Supplement SB—the testing standard that determines if distributed energy resources (DERs) are compliant with the upcoming interconnection standard changes in IEEE 1547-2018. Certain states will require compliance with the new standards as early as Jan 1, 2023, with many others by April 1, 2023. Compliant products from Enphase are already available to ensure you can meet necessary deadlines. Check with your local utility to determine which standards apply and when.

When will Enphase products be compliant with IEEE 1547-2018 requirements?

All components of the Enphase Energy System have been certified by Underwriters Laboratories to be compliant to the IEEE 1547-2018 standard.

  • All solar and battery inverters and the battery are listed with Hawaiian Electric and California Energy Commission.

What is IEEE 1547-2018? 

IEEE 1547 is the National Interconnection Standard used when connecting distributed energy resources (DER) like solar panels, inverters and batteries to the Area Electric Power System (EPS), also known as “the grid.” 

1547 was first published in 2003 and was later codified as a National Requirement by Section 1254 of the Federal Energy Policy Act of 2005.

The second revision of IEEE 1547 was published in 2018 and is referred to as IEEE 1547-2018. This document contains the underlying requirements for interconnection and relies on other companion Standards for testing and certification.

Of note is the addition of the terms “and Interoperability” and “Associated Electric Power Systems Interfaces” in the title of 1547 and in the scope of the Standard.

The interoperability requirements are new in the 2018 edition as well as the requirements for the interfaces needed to implement the new interoperability functionality. These new interoperability requirements have broad implications for many key aspects of our business, the businesses of our installation partners, and the owners of our systems. (See section on interoperability.)

How does 1547 relate to other interconnection rules, codes and standards?

IEEE 1547.1-2020 is the companion testing Standard that is used to verify that the DER includes the capabilities required in IEEE 1547-2018. UL 1741 Supplement SB is the product testing Standard used by testing agencies to evaluate products in order to certify their compliance with IEEE 1547-2018 and 1547.1-2020.

UL 1741 SA versus SB

A key question regarding compliance is what version of UL 1741 is required. All Enphase products are currently evaluated to UL 1741 Supplement SA. 1741 SA was developed to demonstrate compliance with CA Rule 21 and HI Rule 14H. Some utilities, e.g., SRP in AZ, require IEEE 1547-2018 settings and functions but only require evaluation using UL 1741 SA.

Note: UL 1741 SB is written so that completion of an SB evaluation does not invalidate a UL 1741 SA product listing. A product evaluated under UL 1741 SB automatically receives a UL 1741 SA Listing but not vice versa. This was done deliberately to provide manufacturers with a smooth transition path in jurisdictions that initially require UL 1741 SA and later migrate to UL 1741 SB, e.g., CA and HI.

An overview of the relationships between the various Codes, Standards and State regulatory requirements, e.g., California Rule 21, is shown below (graphic courtesy of the Electric Power Research Institute, EPRI).


What are the hardware and communication requirements for Enphase Energy Systems to comply with IEEE 1547-2018?

IEEE 1547-2018 adds new requirements for interoperability. IEEE 1547-2018 defines Interoperability as: The capability of two or more networks, systems, devices, applications, or components to externally exchange and readily use information securely and effectively.

The two main areas of interoperability compliance are separated into hardware requirements and communications protocol requirements.

a. Hardware requirements

IEEE 1547-2018 requires a local DER communications interface located at the DER site. The IQ Gateway provides the local DER interface in Enphase Energy Systems.

IEEE 1547-2018 requires the local communications interface to remain available whenever the DER is operating. This indirectly creates a requirement for the IQ Gateway not to reboot during and following a low voltage ride through event. The IQ Gateway hardware was redesigned to meet this requirement so installers must only choose from the list of supported hardware and be running software versions 7.3.460 or later to be fully compliant.

SKUs that include the new IQ Gateway hardware and will be available for order soon.

Product name SKU Description
IQ Combiner 4 X2-IQ-AM1-240-4 Combiner box with IQ Gateway
IQ Combiner 4C X2-IQ-AM1-240-4C Combiner box with IQ Gateway and cell modem
IQ Gateway ENV2-IQ-AM1-240 Standalone IQ Gateway


Note: Enphase IQ7 and IQ8 Microinverters and IQ Battery 3/3T/10/10T products meet the requirements for IEEE 1547-2018, and when installed with the above supported hardware, according to the provided instructions, create a fully compliant DER System.

Installers and distributors who service New York and New England will have open POs for the existing IQ Combiner and IQ Gateway SKUs automatically transitioned over to compliant SKUs starting in December to receive compliant hardware prior to the earliest possible implementation date.

b. Communication protocols

IEEE 1547 requires the interoperability functions to support one of three communication protocols: IEEE 2030.5, Sunspec (Modbus or TCP), or DNP 3. The protocol used at a given site is specified by the utility.

i. IEEE 2030.5

IEEE 2030.5 has been selected as the interoperability protocol in CA and HI. IEEE 2030.5 appears to be emerging as the defacto national standard interoperability protocol. Enphase products support IEEE 2030.5 via the IQ Gateway.

ii. Sunspec modbus

Sunspec modbus is a legacy protocol commonly used in older equipment and some energy management systems. Enphase support for modbus is under development.

iii. DNP 3

DNP 3 is a legacy protocol commonly used by utilities in large power plants and substation automation. Because it is used in large power plants it may be required in very large, multi-MW systems. We are unaware of any utility which requires DNP 3. Enphase Energy Systems are not designed for or supported at this scale, so we do not presently plan to implement this protocol.

When will IEEE 1547-2018 be required?

IEEE Standards become effective upon publication, but IEEE does not set compliance dates. Compliance dates are set by the Authority Governing Interconnection Requirements (AGIR). The AGIR is normally a public utility commission, public service commission or in some cases the independent system operator. Examples are CPUC (CA), PSC (AZ), ISO-NE (ISO New England).

This is an evolving process. Some compliance deadlines have changed a few times already and may change again.

Mandatory adoption dates

New York and New England ISO (ISO-NE) require compliance as of Jan 1, 2023 . The table below, provides a snapshot of adoption dates that we are monitoring. We will continue to closely monitor the situation and will update this page as new information becomes available.

State IEEE 1547-2018 Adoption Date
New York 1/1/23
New England 1/1/23
Hawaii 2/1/23
California 4/1/23

A map with adoption dates by state is available on this IEEE website. This is maintained by the Electric Power Research Institute (EPRI). It was updated in September 2022. Certain state deadlines herein are out of date and it is expected that EPRI will be updating and republishing the map with appropriate adoption dates.

Which Enphase products are impacted?

The requirements are not retroactive, so sites that are already fully installed do not need to update with new hardware or software. For new installations, based on the compliance date of that location, all Enphase products are impacted by these new Standards, including microinverters as well as IQ Combiner, IQ Gateway, and legacy Envoy-S Metered devices.


  • Three-phase implementations using IQ7 and an NPR (Neutral Protection Relay) box are NOT IEEE 1547-2018 compliant and there is no plan to make them compliant.

  • Envoy S Metered cannot be used to install 1547-2018 compliant systems.

What do Enphase installers need to do to make sure they are meeting IEEE 1547-2018 requirements?

Enphase personnel have been actively involved in the development of IEEE 1547-2018, including participating as members of the committees who created these Standards. The Enphase Energy System has been designed to be able to comply with IEEE 1547-2018. The hardware and SKUs for compliant IQ Gateways and IQ Combiners are changing. The new SKUs are:

Product name SKU Description
IQ Combiner 4 X2-IQ-AM1-240-4 Combiner box with IQ Gateway
IQ Combiner 4C X2-IQ-AM1-240-4C Combiner box with IQ Gateway and cell modem
IQ Gateway ENV2-IQ-AM1-240 Standalone IQ Gateway


Make sure to use the new SKUs listed above for plan submittals.

Other products i.e., IQ7 and IQ8 solar microinverters, IQ Batteries with IQ8X-BAT battery microinverters and IQ System Controller 1/2 only require firmware upgrades to be compliant with IEEE 1547-2018 requirements. IQ Gateway software version 7.3.463 or higher includes the necessary firmware and ensure all the aforementioned components are automatically upgraded to the necessary firmware.

For sites already installed and commissioned, do homeowners or installers need to do anything to update compliance?

No. The requirements are not retroactive, so sites that are already fully installed do not need to update with new hardware or software.

How should installers in California navigate IEEE 1547-2018 and NEM 3.0?

Installers in California should factor in the new net energy metering plan, NEM 3.0, that takes effect on April 14. If you have customers trying to get plans approved under NEM 2.0, make sure you use the new compliant SKUs for IQ Combiner or IQ Gateway to avoid potential rejection of interconnection applications which could impact NEM 2.0 grandfathering. 

What if I install a UL 1741-SB IQ Gateway or IQ Combiner in an area that hasn’t yet adopted IEEE 1547:2018?

UL 1741-SB is a superset that includes compliance with UL 1741-SA, so you can install the compliant IQ Gateway or IQ Combiner in an area that has not yet adopted IEEE 1547:2018.

What happens if I have an interconnection agreement with UL 1741-SA already approved but I install after April 1?

We expect existing approved interconnection agreements will be honored for installation within a year after approval, but check with your utility to be sure.

Where can I find UL certificates of compliance (COC) showing Enphase products have passed UL 1741-SB, 3rd ed?

The best place to retrieve these is from the UL Certification Database website. A free UL account may be required. This site will have the most up-to-date certificates. To find Enphase products that have been evaluated for compliance to UL 1741-SB search file number QIKH.E341165 (NOTE, do not open the Historical document.) Click on the product model link used in your project e.g. IQ8A-72, IQ8PLUS-72 or IQ7PLUS-72.
Occasionally Enphase will post certifications of compliance (CoC) on the documentation center for installer convenience but note that more up-to-date information may be available on the UL site.

How do I show a compliant grid profile in the event I’m asked to do so?

Run and print the System’s Grid Profile Settings Report from the System Report Tab. See Help Topic here:

Where can I find more information about the IEEE 1547:2018 compliant firmware?

Enphase publishes detailed firmware release notes to the documentation center.

Can M Series Microinverter sites have storage retrofits and be IEEE 1547:2018 compliant?

Most systems with M Series Microinverters have a legacy Envoy S. Envoy S products are not IEEE 1547:2018 compliant and will not become compliant. If you wish to add storage to an M Series site with a legacy Envoy S, it could trigger a new interconnection agreement which may require IEEE 1547:2018 compliance and thus require an upgrade to compliant hardware. It will be up to the utility.

Is the CEC listing for IQ7 Series and IQ8H-208V for the single-phase or three-phase versions?

Only the single-phase versions are listed at this time.

Where can I find the recorded webinars with more information about IEEE 1547:2018

The webinar for distributors is available online here: