This article is relevant for users of the expert design experience only.  We recommend not to use this anymore, but you may enable this in your user preferences, by disabling the toggle labeled "Use guided design experience"

The Power Control System feature in Solargraf is designed to enable Inverter manufacturers to control the amount of power (current) flowing through the renewable energy system (PV/ESS). It helps avoid costly upgrades, oversize systems within jurisdiction limitations, and reduce labor effort/cost of the systems.

To delve deeper into the workings of the power control system, refer to this article.

In Solargraf, there are two primary use cases for implementing the Power Control System (PCS):

• Power export limit
• Main panel upgrade avoidance.

The subsequent steps will guide you through the setup process for these functionalities:

Power Export Limit

The first use case, (PEL) refers to the local utility's limit on the amount of energy that the solar system may send to the grid. This limit can only be specified through the energy consumption page.

• Set this up by creating a project and go to the Energy consumption section or go to an existing project’s utility settings.

• In the designated field, enter the Power Export Limit in kilowatts.

• Save your changes by clicking the 'Save' button. Alternatively, if you haven't created the project, proceed to design creation.

Main panel upgrade avoidance

This use case ensures that the reverse feed current from the PV + battery system remains within the current limit of the main panel and can be set up in two ways:

Busbar Power Control

This method curtails solar production based on the maximum allowable current through the main panel’s busbar. The current is the net current flowing through the busbar, including back feed current, current to/from the grid, and current to loads.

• Create a new project or access an existing one.

• Go to to the drawing tool.

• Upon completing your solar design, navigate to the solar design screen. Locate and click on the plug icon situated in the top navigation bar.

This action will initiate further configuration options for your solar and battery grid-tied systems. A window will appear, allowing you to set up the power control system.

This action will initiate further configuration options for your solar and battery grid-tied systems. A window will appear, allowing you to set up the power control system.

• Fill out the fields for Main Panel Busbar Rating, Main Service Breaker Rating, and DER/Backfeed breaker rating.

• Toggle on/Enable the power control system.

Calculate Current Limit using NEC 120% Rule

This method curtails solar production based on 120% of the combined main panel busbar rating and service breaker rating.

• Create a new project or access an existing one.

• Go to to the drawing tool.

• Upon completing your solar design, navigate to the solar design screen. Locate and click on the plug icon situated in the top navigation bar.

This action will initiate further configuration options for your solar and battery grid-tied systems. A window will appear, allowing you to set up the power control system.

• Fill out the fields for Main Panel Busbar Rating and Main Service Breaker Rating.

• Click on the interrogation icon for guidance on locating this information on the main panel.

• Toggle on the power control system.

• Save your settings and proceed with the design.

Enter Current Limit

This option curtails solar production based on the maximum allowable backfeed current.

• Create a new project or access an existing one.

• Go to to the drawing tool.

• Upon completing your solar design, navigate to the solar design screen. Locate and click on the plug icon situated in the top navigation bar.

This action will initiate further configuration options for your solar and battery grid-tied systems.A window will appear, allowing you to set up the power control system.

• Set up the PCS controlled current limit.

• Toggle on the power control system.

• Save your settings and proceed with the design.

Tips for Using PCS (Power Control System) Feature:

• You can learn more about about how PCS works by clicking on know more.

• You may reset all inputs by clicking on the button seen below.

• To observe the influence of the PCS feature on production, simply click on the interrogation icon adjacent to the production value within the drawing tool.

PCS States

When configuring PCS settings for your project in Solargraf, understanding the three distinct states is important. Each state holds specific significance, and we'll delve into their meanings below:

No indication on the PCS tool - Suggests either the absence of panels or that the designed system is within PCS limits. No action is required in this case.

The red state indicates that the designed system exceeds PCS limits. To correct this, you can either enable the Power Control toggle or consider upgrading the main panel and ignoring PCS.

The green state indicates that the designed system exceeds PCS limits, and PCS is enabled. No action required in this case.