The SigenMicro AC Trunk-40P-1.1M-4.0 (MPN 14280066) is the pre-terminated AC bus cable used to link a string of SigenMicro microinverters, with connectors moulded on at a tight 1.1m interval to suit closely spaced installations. As with the standard trunk cable, no on-site crimping is needed — the cable is simply run along the array and cut to length where required.
This variant is built for portrait-oriented PV modules, where microinverters sit closer together along each row. It ships with 40 pre-fitted connectors across a 44m total length, giving enough connection points for longer portrait strings without needing extra couplers.
Conductor cross-section on this variant is the larger 4.0mm², chosen where a run carries more microinverters, a longer overall AC bus length, or where minimising voltage drop along the trunk matters — for example on larger UK rooftop arrays approaching the system's parallel connection limits. Every joint uses the same locking connector system as the rest of the SigenMicro kit, so trunk sections, couplers and terminators all click together without tools other than the dedicated unlock tools.
Portrait
PV Module Orientation
Cut-to-Length
On-Site Trimming
Please Note
The 4.0mm² conductor is intended for longer or higher-current AC bus runs, where the thicker cable helps limit voltage drop across the string. For shorter runs or smaller arrays, the 2.5mm² SigenMicro AC Trunk-40P-1.1M-2.5 may be more cost-effective — check your installation's cable run length and number of parallel microinverters before choosing between the two.
Pre-Terminated Connectors
Arrives with 40 connectors already moulded onto the cable at fixed 1.1m spacing, removing the need for on-site crimping or splicing.
Cut As Needed
The 44m integrated trunk can be cut to length on installation, so a single reel covers rows of varying size without waste stock of multiple fixed lengths.
Heavier Gauge for Longer Runs
The 4.0mm² conductor is sized for longer AC bus runs and larger microinverter strings, helping keep voltage drop within limits on bigger UK rooftop installations.
Matched to Portrait Layouts
The 1.1m interval is designed around portrait PV module widths, keeping each connector aligned directly under its microinverter along tighter row spacing.
Weatherproof Locking Connectors
Uses the SigenMicro locking connector system, compatible with the dedicated AC Trunk Unlock Tool and AC Trunk Port Cap for a fully weatherproof rooftop run.
Extendable with Couplers
Additional length beyond the standard reel can be added using the SigenMicro AC Trunk Coupler, joining trunk cable to further trunk cable or field-supplied AC cable.
Cable
Product Code
SigenMicro AC Trunk-40P-1.1M-4.0
Conductor Diameter
4.0 mm²
Number of Connectors
40 pcs
Recommended Layout
Portrait PV modules
Compatibility
Used With
SigenMicro 400 / 500 / 800 / 1000W microinverters
Compatible Accessories
SigenMicro AC Trunk Coupler, AC Trunk Port Cap, AC Trunk Terminator, AC Trunk Unlock Tool
Installation
Rooftop solar, multi-microinverter strings, larger UK arrays
Important Safety Information
AC trunk cable installation and grid connection must be carried out by a qualified electrical installer in accordance with local wiring regulations. The distribution panel's AC switch rating and the number of microinverters connected in parallel should be checked against the manufacturer's technical parameters before selecting cable gauge.
What is the difference between the 2.5mm² and 4.0mm² versions of this trunk cable?
Both use the same 1.1m connector interval and 40-connector count for portrait layouts, but the 4.0mm² version has a thicker conductor, better suited to longer AC bus runs or larger strings where voltage drop needs to be kept lower.
When should I choose the 4.0mm² trunk cable over the 2.5mm² version?
Choose the 4.0mm² version for longer cable runs or where a large number of microinverters are connected in parallel on the same AC bus, since the heavier gauge helps limit voltage drop over distance.
Can this trunk cable be cut to a shorter length?
Yes. The cable is described by the manufacturer as "cut as needed", so installers can trim the 44m trunk down to match the exact roof run required.
What do I do with unused connectors at the end of a run?
Fit a SigenMicro AC Trunk Port Cap over any unused connector, or a SigenMicro AC Trunk Terminator at the physical end of the cable run, to keep the connection weatherproof.
Which microinverters is this cable compatible with?
It is designed for the SigenMicro 400, 500, 800 and 1000W microinverter range.
