Rapid shutdown lowers the voltage on PV conductors after an initiator is operated. Its purpose is to reduce shock hazard for first responders working in and near the array. SMA US inverters are listed under UL 1741 as rapid shutdown equipment only. A complete system also needs PV array disconnect switches and an initiator, which is usually the AC disconnect. When shutdown starts, the inverter stops sending the SunSpec permission-to-operate signal. On the Sunny Boy Smart Energy, the parameter Operation.RSSInitiator selects the initiator: either the AC disconnect or a digital input. Generac PV Link handles shutdown of the conductors leaving the array. For 2017 and 2020 NEC compliance, one SnapRS per module must be added and the Enable PVRSS setpoint turned on (it ships off). Enphase IQ8 systems without an IQ System Controller can use the PV or service disconnect as the initiator. In multimode with IQ System Controller 2, the Enphase DPST System Shutdown Switch is required instead. If the IQ System Controller stays in rapid shutdown or reports a rapid shutdown error, check the wiring of the rapid shutdown switch.
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requiresc1 drafted · lead Generac PV Link
Scope: products Generac SnapRS
SnapRS devices must be paired with the Generac S2502 PV Link to make a complete PVRSS under NEC 690.12.
sec=h13 h=47cb3f937df4sec=h34 h=6272feef1a7cc2 drafted · lead Enphase IQ System Controller
Scope: products Enphase IQ8 Series Microinverters proposed
Applies only when IQ8 is commissioned in multimode with IQ System Controller 2. A DPST rapid shutdown switch wired to the controller then initiates the shutdown.
sec=h1 h=c48b7a84e4fdsec=h5 h=43e7a83bbfc8c3 verified · fact SunSpec rapid shutdown signal
Applies when SunSpec-compliant PV array disconnect switches are installed. The inverter sends a permission-to-operate signal over the DC conductors and stops sending it when shutdown is initiated.
sec=h1 h=46538d48fa94sec=h79 h=e0da560c67b6sec=4.5.10 h=aea2d80fffb7sec=h76 h=f47c5bb7909csec=h80 h=813c727c3285sec=h68 h=eea7971c997dsec=h1 h=fbcb8e01281bverified by: review-workflowverified on: 2026-10-24
trip_thresholdConditions: DC conductors after rapid shutdown, complete PVRSS built around an SMA US inverter
sec=h1 h=46538d48fa94sec=h79 h=e0da560c67b6sec=4.5.10 h=aea2d80fffb7sec=h76 h=f47c5bb7909csec=h80 h=813c727c3285sec=h68 h=eea7971c997dsec=h1 h=fbcb8e01281bConditions: Controlled conductors leaving the array, as Generac reports the NEC 2014 requirement
tbl=9.r2 h=5fa721a7779btbl=9.r2 h=5fa721a7779btbl=9 h=81b573c049b6Conditions: Controlled conductors leaving the array, as Generac reports the NEC 2017/2020 requirement
tbl=9.r3 h=92c7a0443ae4tbl=9.r3 h=92c7a0443ae4tbl=9 h=81b573c049b6Conditions: Controlled conductors inside the array boundary or within 1 m (3 ft) of the building penetration point, as Generac reports the NEC 2017/2020 requirement
tbl=9.r3 h=92c7a0443ae4tbl=9.r3 h=92c7a0443ae4tbl=9 h=81b573c049b6Scope: products Generac SnapRS
Conditions: Controlled conductors within the 1 ft (305 mm) array boundary, SnapRS used with PV Link
sec=h31 h=59459794ebbesec=h48 h=aa7cf8059dcaScope: products Enphase IQ8 Series Microinverters proposed
Conditions: Rapid shutdown state of IQ8 microinverters after initiation through IQ System Controller 2
sec=h5 h=43e7a83bbfc8trip_timeConditions: Time for an SMA-based PVRSS to bring DC conductors below 30 V
sec=h1 h=46538d48fa94sec=h79 h=e0da560c67b6sec=4.5.10 h=aea2d80fffb7sec=h76 h=f47c5bb7909csec=h80 h=813c727c3285sec=h68 h=eea7971c997dsec=h1 h=fbcb8e01281bverified by: review-workflowverified on: 2026-10-24
Conditions: PV array disconnect switches disconnecting the array from an SMA inverter after initiation
sec=h1 h=46538d48fa94sec=h79 h=e0da560c67b6sec=4.5.10 h=aea2d80fffb7sec=h76 h=f47c5bb7909csec=h80 h=813c727c3285sec=h68 h=eea7971c997dsec=h1 h=fbcb8e01281bverified by: review-workflowverified on: 2026-10-24
Conditions: Controlled conductors leaving the array, as Generac reports the NEC 2014 requirement
tbl=9.r2 h=5fa721a7779btbl=9.r2 h=5fa721a7779btbl=9 h=81b573c049b6verified by: review-workflowverified on: 2026-10-24
Conditions: Controlled conductors inside and outside the array, as Generac reports the NEC 2017/2020 requirement
tbl=9.r3 h=92c7a0443ae4tbl=9.r3 h=92c7a0443ae4tbl=9 h=81b573c049b6Scope: products Generac SnapRS
Conditions: SnapRS used with PV Link, measured from rapid shutdown initiation
sec=h31 h=59459794ebbeScope: products Enphase IQ8 Series Microinverters proposed
Conditions: Transition of IQ8 microinverters to the rapid shutdown state
sec=h5 h=43e7a83bbfc8response_timeScope: products Generac PV Link, Generac SnapRS
Conditions: PV Link and SnapRS response after rapid shutdown initiation (shutdown time of the RS801, RS801A and RS802)
tbl=4.r6 h=b8913ecab63asec=h48 h=aa7cf8059dcasec=h47 h=2355b3727d6arelated_to c1related_to c5related_to c3implements c7lacks c8implements c3implements c11requires c7implements c3implements c2implements c2implements c2implements c3part_of c1