SwitzerlandGuides · Updated on 11.09.2026
OIBT Inspection of a Photovoltaic Installation
A grid-connected photovoltaic installation is a fully-fledged electrical installation. It undergoes a final inspection by the contractor, followed by an acceptance inspection by an independent body, before the grid operator gives final approval to feed power into the grid.
Final inspection and acceptance inspection
The contractor carries out the final inspection and measurement report for its own installation. The acceptance inspection is carried out by an independent body: it checks the DC side (strings, disconnect switches, protection devices), the inverter, the connection to the panel and the earthing.
What the inspector measures
Open-circuit voltage and short-circuit current of each string, DC-side insulation resistance, continuity of equipotential bonding, operation of the protection devices and inverter disconnection, markings and labeling.
Documents to provide
Installation notice approved by the DSO, installation diagram, technical data sheets for the modules and inverter, the contractor's measurement report. The safety report from the acceptance inspection is submitted to the DSO; Pronovo may request it for the one-off subsidy.
Existing installations
A PV installation then follows the inspection interval of the building that hosts it. During the periodic inspection of an equipped house, the solar part is inspected at the same time; the flat rate takes the installed capacity into account.
Batteries and charging stations
Battery storage and charging stations are inspected along with the installation. OIBT pro offers dedicated flat rates, from CHF 402 for a battery and from CHF 376 for a charging station.
Frequently asked questions
Is the acceptance inspection mandatory for a small installation?
The grid operator requires a safety report for any connected installation; inspection by an independent body is required for power-generating installations. Check your DSO's conditions on the installation notice.
Can the contractor carry out the acceptance inspection itself?
No: the acceptance inspection must be independent of the company that carried out the installation.
How long does the inspection take?
One to two hours for a residential 10 kVA installation, depending on the number of strings and roof accessibility.