Pv Load Center Configuration And Location; Key Components Of Pv Load Center - enphase IQ8 Design Manual

4. When transitioning between rows for the same AC branch circuit, go across rows with the use
of three-phase field wireable (QD-CONN-10F and QD-CONN-10M) connectors along with
Raw QD Cable to extend the cable drop length. Try to minimize unused/skipping QD
connectors in the Branch circuit to maintain phase balance across each phase.
•
Each connector on the QD Cable is marked with Phase ID C1, C2, and C3, which shows
the phase rotation across the connectors in the QD Cable as shown in Figure 4, and the
similar phase rotation arrangement continues across the cable.
•
Plan your AC branch circuits with a maximum recommended IQ8 Commercial
Microinverters per branch circuit. In case you are skipping a connector, ensure that each
branch circuit has IQ8 Commercial Microinverters as multiples of 3 per phase, that is, L1-
L2, L2-L3, L3-L1 and within the maximum recommended number of microinverters per 3-
pole 20 A circuit. You can check the marking on connectors C1 (L1-
C3(L3-L1) to count the number of microinverters per phase in a branch circuit when
protected with a 3-pole 20 A over-current protection device (OCPD).
•
If one exceeds the limit of IQ8 Commercial Microinverters per phase (L-L) in a branch
circuit (IQ8P-3P: 4 microinverters, IQ8H-3P: 5 microinverters), then the current will be
more than QD Cable capacity. For more details, refer to Appendix A: Ampacity
calculations for IQ8 Commercial Microinverter system.
•
In case you are skipping a connector, ensure you have an equal number of C1, C2, and C3
in the system to maintain the power balance across phases achieved using the phase
rotation in QD Cable.
5. Enphase recommends that the total percentage of voltage rise in the AC wiring be a maximum
of 2%, with (an inclusive) less than 1% voltage rise in the QD Cable.
6. It is recommended to use Center feeding of the AC branch circuit to reduce voltage rise
when QD Cable voltage rise is >1%.
7. QD Cable is a UL3003 DG (Distributed Generation) listed cabling system. The DG cable
standard UL3003 is based upon the construction specifications (wet-rated) of TC-ER cable,
which may be installed in the raceway as per NEC 336.10(3).
8. You must install supports (such as clips) for the QD Cable and Raw QD Cable at 1.8 m (6 ft)
intervals or less. Installation requirements for wet-rated cable allow QD Cable and Raw QD
Cable to be installed in conduits, cable trays, and other raceways.

3.3 PV load center configuration and location

A PV load center enables dedicated isolation of the microinverter branch circuits and provides a simple
installation platform for the IQ Gateway Commercial 2.
The PV load center should be installed considering both the cable route and distance to the
microinverters. You can install the PV load center indoors or outdoors, depending on the electrical
layout across the site.

3.3.1 Key components of PV load Center

•
PV load center enclosure: The PV load center enclosure may be indoor or outdoor rated,
depending on the installation location of the load center onsite.
•
IQ Gateway Commercial 2.
•
Dedicated IQ Gateway Commercial 2 circuit.
•
Production CTs (Current Transformers).
•
Three-phase circuit breakers.
30
IQ8 Commercial Microinverter grid-tied PV system
© 2023 Enphase Energy Inc. All rights reserved.
L2), C2(L2-L3), and
November 2023
USG-00026-1.0