enphase IQ8H-3P-72-E-US User Manual

IQ8 Commercial Microinverter grid-tied PV system
22 © 2023 Enphase Energy Inc. All rights reserved. November 2023
USG-00026-1.0
The following table lists the different scenarios based on the starting point of the circuit using QD
Cables and the possible number of microinverters, which could be on either side of the center tap.
Table 14: QD Cable variants
IQ8P-3P IQ8H-3P
Start
from
connector
Circuit size Center tap
Start from
connector
Circuit
size
Center tap
1 12 6,6 1 15 6,9
2 12 5,7 2 15 5,10
3 12 4,8 3 15 10,5
4 12 3,9 4 15 9,6
5 12 8,4 5 15 8,7
6 12 7,5 6 15 7,8
1 9 NA 1 12 6,6
2 9 NA 2 12 5,7
3 9 NA 3 12 4,8
4 9 NA 4 12 3,9
5 9 NA 5 12 8,4
6 9 NA 6 12 7,5
1 9 NA
2 9 NA
3 9 NA
4 9 NA
5 9 NA
6 9 NA
Though we recommend a maximum of nine connectors on either side of the center tap, there are two
instances with IQ8H-3P where the QD Center Taps have ten on either side, especially when the installer
starts from connectors 2 and 3. This is acceptable as per the VRise table (refer to Table 13).
2.3.4 Advantages of center feeding QD Cable AC branch circuit
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. A fully populated IQ8 Commercial branch
circuit has 12 microinverters with IQ8P-3P and 15 microinverters with IQ8H-3P on the AC Branch circuit.
As voltage rise is exponential, reducing the number of microinverters in the branch circuit greatly
reduces the voltage measured at the farthest microinverter in the branch. One way to minimize this
voltage rise is to center feed the branch, that is, divide the circuit into two subbranch circuits protected
by a single OCPD. Therefore, for all installations with IQ8 Commercial Microinverters, center feeding of
three-phase AC supply is recommended.
All three QD Cable SKUs include center-tapping connectors after every 6 AC male QD connectors in
the QD Cable spool. The center tap connectors are sealed with a sealing cap, and the sealing cap
should be removed only when the connector is used for feeding the AC supply to the branch.

enphase IQ8H-3P-72-E-US Specifications

General

Brand	enphase
Model	IQ8H-3P-72-E-US
Category	Inverter
Language	English