enphase IQ System Controller 3M Quick Install Manual page 30

Section C - Wiring
Control (CTRL) wiring
between system components
Control wiring guidance for the Enphase Energy System:
Refer to the following wiring sequences to understand the position
of the header with termination resistor, wiring order, and drain wire
termination location.
NOTE: Ensure the following guidelines are followed to avoid
failures during system commissioning:
• The drain wire should only be terminated on one end of
the control wiring between system components.
• It is recommended that the drain wire be terminated at the
component from which the control wiring for the section is
initiated.
• The same conduits can be used for power and control wire
routing only when using an Enphase CTRL cable, that is,
CTRL-SC3-NA-01.
The following are the common wiring sequences:
Sequence 1: IQ Combiner 5/5C → IQ Battery(s) 5P → IQ System Controller 3M → IQ Meter Collar
NOTE: The total length of CTRL wiring across the system cannot exceed 250 feet to ensure the system operates as
per specifications.
WARNING: The drain wire should only be terminated on one end of the control wiring between the system
components to prevent ground loops.
30
Always wire IQ Meter Collar to
top connector of
IQ System Controller 3M
since it contains 24 V source
for the IQ Meter Collar
IQ System Controller 3M quick install guide