Enphase IQ System Controller 3
The IQ System Controller 3 is the automatic transfer switch and grid-form controller for an Enphase backup install. It's what turns a basic grid-tied PV system into one that keeps the lights on when the utility goes down.
- Type
- Automatic transfer switch + grid-form controller
- Function
- Islands home during grid outage, signals microinverters and batteries to grid-form
- Warranty
- 5-year Enphase
- Enclosure
- NEMA 3R (outdoor)
- Transition
- Milliseconds (UPS-style no-break)
- Configuration
- Between main service panel and backup loads panel
About this item
The IQ System Controller 3 is the automatic transfer switch and grid-form controller for an Enphase backup install. It's what turns a basic grid-tied PV system into one that keeps the lights on when the utility goes down.
The Controller monitors the grid 24/7. When the grid drops, it islands the home in milliseconds and signals the IQ8 microinverters and IQ Battery 5P units to grid-form. The microinverters now follow the battery instead of the grid, the batteries push real power into the panel, and the install keeps the protected loads up without an outage interruption. When the grid comes back, the Controller re-synchronizes and folds the system back into the grid.
Sits between the main service panel and a backup loads panel. Sized for whole-home or critical-loads backup depending on how the loads are wired. Pairs with the IQ Combiner 5C and IQ Battery 5P for a complete Enphase backup stack. NEMA 3R outdoor mount, 5-year Enphase warranty.
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