enphase IQ System Controller 3M - Section D; Power Control System (PCS); Introduction

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IQ System Controller 3M quick install guide IQ System Controller 3M quick install guide
Section D
Power Control System (PCS)
Introduction
The Enphase Energy System supports four Power Control System (PCS) use cases:
1. Main panel upgrade (MPU) avoidance mode: This feature limits the backfeed current to the main panel based on either the breaker
limit (or) the sum of current sources entering into the busbar of the main panel.
When MPU avoidance with Busbar Overload control is enabled, the Enphase Energy System limits backfeed current by controlling
the sum of current into the busbar as per National Electric Code (NEC) 2020 705.13 (A) through (E). Busbar overload control
monitors backfeed current to the main panel by DERs and current owing in from the grid and ensures the sum of both at all times is
less than the rating of the main panel busbar.
When MPU avoidance using the NEC 120% rule, the Enphase Energy System limits only the backfeed current, as per 705.12, Section
(B) (3). In this case, the most common rule as shown below is applicable: ((120% of busbar rating) - Ampacity of the overcurrent
protection device protecting the busbar)/125%.
Enphase recommends using MPU Avoidance with Busbar Overload control to maximize the renewable energy available and minimize
any draw from the grid.
2. Battery import-only or export-only mode: IQ Battery 5P can be congured in either one of two battery modes: Battery import-only
mode or Battery export-only mode.
Battery import-only mode ensures the IQ Battery 5P never exports any power to the grid. Without this mode, some utilities may
require the installation of an additional Net-generation output meter (NGOM) for sites with battery sizes above 10 kW. This feature
reduces the cost of installation for the homeowner. Battery import-only, after conguration, applies regardless of the congured
battery smart prole, i.e., self-consumption, full backup, or savings (time of use) with optimization.
Battery export-only mode allows Enphase IQ Battery 5P to export to the grid but ensures it never imports from the grid. Homeowners
can benet from a lower payback period by storing excess PV power during o-peak hours and discharging the stored energy to the
grid during the time when it is most benecial to the homeowner based on the import and export tari rates.
Export-only mode is the recommended mode for Net Billing Tari (NBT) or Net Energy Metering 3.0 (NEM3.0) sites.
3. Aggregate power export limit mode: This feature ensures that the aggregate power exported to the grid is limited to the aggregate
power export limit (PEL) dened by the installer.
4. IQ Battery oversubscription mode: This feature allows for more IQ Batteries to be installed against a given IQ Battery breaker in the
IQ System Controller by ensuring that the total continuous output current from the IQ Batteries on the battery port does not exceed
80% of the battery breaker rating.
IQ SYSTEM CONTROLLER SKU MAX NO. OF IQ BATTERY P PORTS SUPPORTED
MAXIMUM ENERGY
KWH
MAXIMUM POWER
KW
SC200D111CMC1US01 16* IQ Battery and DER 80 kWh 30.72 kW
*Maximum of eight each on IQ Battery port and additional IQ Battery port (DER port).