Permission to operate, or PTO, is the approval a system needs after installation and inspection before it may run normally connected to the grid. The utility usually gives this approval as a PTO letter from its interconnection group, and incentive programs such as SGIP accept that letter as proof of authorization to interconnect. While a Generac PWRcell system waits for PTO, it can either run with Export Override on, so it sends no power to the grid, or stay fully disabled. If a battery system with a protected loads panel is left disabled while waiting, keep the inverter grid breaker and the Protected Loads Disconnect on so the protected loads still get power. On SMA inverters, the system operator can withdraw permission to operate with the stop operating mode, which sends the inverter into standby or a locked state. Do not confuse PTO with the SunSpec rapid shutdown keep-alive, which is also called a permission to operate signal and stops during a grid outage.
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related_toc1 verified · fact Interconnection process
A PTO letter emailed by the utility's interconnection group serves as proof of authorization to interconnect.
tbl=6.r3 h=78ea594dc6f0verified by: review-workflowverified on: 2026-10-24review note: support check: partial - The passage shows a PTO letter emailed from utility interconnection as proof of authorization to interconnect, but does not name the interconnection process concept explicitly beyond this.
c2 verified · fact Utility approver
The PTO letter is issued by the utility's interconnection group.
tbl=6.r3 h=78ea594dc6f0verified by: review-workflowverified on: 2026-10-24
c3 drafted · lead Export limitation
While a PWRcell system waits for PTO, it may run with Export Override turned on so that it does not export to the utility grid.
sec=h144 h=14dc7efc4743sec=h132 h=14dc7efc4743c4 drafted · lead Generac PWRcell Inverter (X7602, XVT076A03, XVT114G03)
The manuals describe two allowed system states before PTO (operating without export, or disabled) and how to activate the system once PTO is granted.
sec=h144 h=14dc7efc4743sec=h132 h=14dc7efc4743tbl=2.r21 h=a012a9f52942review note: support check: partial - The two pre-PTO states are described, and the heading on activating post-PTO appears, but the activation steps are not given in the passages.; review: partial - Both Generac passages describe the two allowed states while awaiting PTO, but the note's claim that they explain how to activate the system after PTO rests only on a section heading and a table-of-contents line; no activation steps are quoted.
c5 drafted · lead Area EPS operator proposed
In SMA operating-state descriptions, the system operator can withdraw permission to operate (Operation.OpMod = Stop).
tbl=19.r9 h=cbc82bbd61betbl=19.r11 h=193a7c9f3deetbl=19.r8 h=565db8fcf0bdAn SMA inverter moves from RUN to STANDBY when the system operator withdraws permission to operate.
tbl=19.r8 h=565db8fcf0bdverified by: review-workflowverified on: 2026-10-24
c7 drafted · lead SunSpec rapid shutdown signal
This is a separate meaning of the term: the SunSpec rapid shutdown keep-alive is called a 'permission to operate' signal. It is not the utility approval.
sec=h15 h=71680ad772d9related_to c3