PV Generation with Microinverters PV Generation with Microinverters

Microinverters are installed behind each solar module and convert the DC power from solar modules to grid-compliant AC power right at the module. Use our data sheets and design resources below to help you design your system. For more information about Enphase Microinverters, visit the Microinverter Family page of our website.

 
Designing Systems with the Enphase  Microinverter

In this video, we review the steps required to design a system with the Enphase Microinverters.

Selecting the Right Microinverter

To determine the compatibility of specific PV modules with Enphase Microinverters, use our Module Compatibility Calculator.

Review specifications and design resources for each of our Microinverters below.

Array Sizing

To determine how many microinverters you'll need simply divide the desired AC system size by the nameplate rating of the compatible microinverter. For example, if you're designing a 7.56kW AC system using the S270 Microinverter, divide 7,560 by 270 to arrive at 28 microinverters. (7,560 / 270 = 28)

AC Branch Circuits

The maximum number of microinverters that can be installed on each AC branch circuit can be found in a microinverter's datasheet. Continuing the example from above, the maximum number of S270 single-phase microinverters that can be installed on a 20A circuit is 14. This means that you'll need two branch circuits for this 7.56kW sample system. (28 / 14 = 2)

System Compatibility

If creating a system with a Enphase AC Battery expansion in mind for the future, it should be noted that a Envoy-S Metered is required.

If creating a system with zero-export capabilities in mind, it should be noted that an Envoy-S Metered gateway must be paired with S-Series Microinverters. Other string systems paired with the Envoy-S Metered gateway are incapable of doing zero export.

Commercial Support

Enphase provides customer service, training and engineering staff to assist deployment of Enphase products in the APAC region.

When installing grid connected solar in a commercial application within Australia, installations must be signed off by a CEC Accredited Designer and installer. Both the designer of the system and installer must be trained to specify, and install, Enphase products.

Interconnection rules and regulations for commercial sized solar installations (typically for systems greater than 15kVA in capacity), can be stringent.

Commercial size systems present extra challenges such as:

  1. Single Line Drawings
  2. Site Layout Drawings
  3. DNSP Network Connection requirements (e.g export limiting, power factor, phase balancing, grid protection settings), normally referenced as Embedded Generation on the relevant DNSP websites.
  4. Secondary Protection Systems (Network Protection)
  5. DNSP Interconnection and testing Approval
  6. Injection Testing
  7. Multiple Points of connection
  8. Commissioning documentation

Enphase engineering can review design drawings and provide guidance where required.   However, Enphase recommendations using an experienced solar engineering service to design and specify commercial projects where the Accredited Designer and Installer may not have the experience or technical expertise. Enphase staff do not design systems and are not a substitute engineering service. Speak to your account manager about how Enphase can help with your next commercial project.

Microinverter Resources

S230
5th generation product supporting 60-cell modules. Commonly paired with modules in range of 195 W - 285 W.
S270 
5th generation product supporting 60-cell and 72-cell modules. Commonly paired with modules in range of 230 W - 350 W.

Communications and Control with Envoy Communications and Control with Envoy

The Envoy is the monitoring and control appliance for the system, and it communicates with system components over the AC power lines at the site. If the Envoy is unable to communicate with system components, operations may be impaired.

Follow best practice for placement design and installation of the Envoy to ensure reliable system monitoring and control. Design plans should call for the installation of the Envoy on its own circuit at the PV sub-panel.

The Envoy-S Metered ships with one production CT and one consumption CT for sites requiring revenue grade metering and consumption monitoring. Both CTs are required for storage systems. If you are installing a Envoy-S Metered for a multiphase system, you will need purchase additional CTs as appropriate.

Review specifications and design resources for the different types of control component installations.

Energy Storage with AC Battery Energy Storage with AC Battery

The Enphase Storage Solution is modular by design and may be sized to meet your customer's current needs and may be expanded in the future as their needs change. The Enphase solution is PV technology agnostic and may be installed on an Enphase Microinverter System or a string system installed years ago, before microinverter technology became available.

The Enphase Storage Solution requires installation of the Envoy with production and consumption metering CTs for AC Battery charge and discharge control.

Visit our Storage System page for more information about the Enphase AC Battery, and review specifications for the AC Battery below.

Sizing the the Enphase Storage Solution

The homeowner's Energy Storage Solution can be sized to meet their storage goals using the Enphase Storage Sizing Tool.

To access the storage sizing tool, you will need to have an Enlighten Manager account. If you do not already have an Enlighten account, please visit our Setup page to learn how to create your account. Once logged in to Enlighten, you can access the Storage Sizing Tool on your Dashboard. If you do not see the Storage Sizing Tool widget, click Add Widget on the upper right on your Dashboard to add it.

System Compatibility

The Enphase AC Battery is AC-coupled and therefore system agnostic. You can retrofit this solution onto any pre-existing solar system regardless of inverter architecture. For multiphase AC Battery installations, you'll need to ensure you have enough additional production and consumption CTs to cover each phase.