The safety certificate (SiNa) is the confirmation that the electrical installation of a solar system has been carried out professionally and in accordance with standards. It is issued during installation by the executing specialist company and is part of the ordinary registration to the grid. Later, the system – like every electrical installation – is periodically inspected at regular intervals. Both ensure that the system remains safe. (As of: July 2026)
Key points in brief
- SiNa stands for safety certificate: the documented confirmation of a safe, standard-compliant electrical installation.
- It is issued during installation and belongs to the connection of the system to the grid.
- It is issued by the executing, licensed specialist company – not by the owner.
- After that, the system is subject to periodic electrical inspection at regular intervals.
- For you as the owner, it is important to keep the documents safe and not ignore the inspection request from the grid operator.
What is the SiNa – and what is it for?
The safety certificate is a document that confirms: This electrical installation was carried out according to the applicable standards and is safe. For a solar system, this concerns the entire electrical system – from the modules to the inverter to the connection in the house distribution board.
You can understand the SiNa as the «attestation» of the system. It is not simply claimed, but is based on an inspection of the work carried out. The specialist company checks whether everything is wired, earthed and protected correctly, and records the result. Only with this proof is the installation considered proper by the grid operator.
Thus, the SiNa is not bureaucratic padding, but the safeguard that the system endangers no one – neither through an error in the installation nor in later operation. How the electricity flows in detail from the modules to the house distribution board and which protective devices interact in the process is shown in the article on the electrical system of the solar system.
Who issues the SiNa, and when?
The SiNa is issued during installation – by the executing specialist company that has the necessary installation authorisation. For you as the owner, this is reassuring news: You do not have to worry yourself about everything being documented in accordance with standards. That is the task of the company connecting the system.
This exact point is important when choosing a provider. Only a licensed electrical specialist company may carry out the electrical installation and issue the safety certificate. Anyone who has a system installed by a provider without this authorisation risks problems with the proof and the grid connection – one reason why the question about the installation authorisation is part of checking a provider, as described in the article on foreign providers.
The process in brief:
1. The specialist company carries out the electrical installation. 2. After completion, the installation is inspected and the safety certificate is issued. 3. The proof goes to the grid operator as part of the registration; the system is connected to the grid. 4. Within six months, an acceptance inspection by an independent inspection body additionally follows for grid-connected systems – formally a duty of the ownership, in practice the serious specialist company helps organise it. 5. You receive the documents for your files.
What is the periodic inspection – and how often?
The SiNa during installation is not the end of the story. Every electrical installation in Switzerland is subject to a periodic inspection – so it is not checked just once, but at regular intervals. This applies to the house installation as well as to the solar system as part of it: According to the ESTI directive on photovoltaic systems, the system is subject to the same inspection period as the electrical installations of the building to which it is connected. For a purely residential building, this is usually 20 years; commercially used properties are inspected much more frequently depending on the use, and in the case of mixed use, the shorter period applies.
In practice, it works like this: After the respective inspection period has expired, the grid operator asks the ownership to have the installation checked by an independent, authorised inspection body. This body issues a new safety certificate confirming that the system is still in order. Any defects must be rectified.
| Safety certificate upon installation | Periodic inspection | |
|---|---|---|
| When | once, at initial installation | recurring after the end of the inspection period |
| Who commissions | the specialist company during the installation | the ownership, requested by the utility |
| Who carries it out | executing specialist company | independent, authorised inspection body |
| Result | System is connected to the grid | renewed proof, defects are rectified |
Orientation, as of: July 2026. The specific inspection period and the requirements result from the applicable regulations and the request of your grid operator.
For you as the owner, the practical core is simple: keep the documents of the system safe and do not let the inspection request from the grid operator disappear into the filing cabinet. Anyone who ignores it risks reminders – and in doubt, the safety of the installation is questionable.
The safety certificate is invisible for most customers – and that is a good thing, because we take care of it during installation. Where we repeatedly start is storage: The documents for the system belong with the house files, not in the wastepaper basket. And when years later the request for a periodic inspection arrives, it is no reason to worry, but routine – just like with the rest of the house electrical system. We often experience that this request is left lying around because no one knows what it means. That is why we address it during the handover: It will come, and it is normal.
Frequently asked questions
Do I have to issue or commission the SiNa myself?
During installation no – the executing specialist company takes care of that as part of the connection. Only at the later periodic inspection will you, as the owner, be asked by the grid operator to initiate an inspection by an authorised inspection body. The first proof is therefore a matter for the installer, the recurring one yours.
What happens if I ignore the inspection request?
The grid operator usually issues a reminder and sets deadlines. In essence, it is about the safety of the installation, which is why the inspection is not optional. It is worth taking care of the request promptly instead of putting it off – the inspection itself is routine.
Is the periodic inspection for a solar system extensive?
It is part of the already due inspection of the house electrical system and no special effort just for the system. An authorised inspection body checks the installation and issues a new safety certificate. If defects are found, they must be rectified – with a professionally built system, this is the exception.
Do I need the SiNa when selling the house?
Yes, the documents for the system including the safety certificate are among the documents handed over upon sale. A complete file folder for the system makes the takeover easier for the buyers and shows that the installation was carried out and inspected properly.
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Professionally installed, cleanly documented
The electrical installation of your system is carried out by a company with an installation authorisation – ecoEn is itself registered with ESTI for this (Art. 14 NIV, No. SOB-284349-1) – and you receive the safety certificate with all documents.
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Photovoltaics Switzerland – installation by a specialist company →
Swissolar-certified specialist company · ESTI installation authorisation (Art. 14 NIV) · in Zurich since 2017 · over 150 systems completed · a personal answer from the specialist company, no call centre
Sources: ESTI directive No. 233 «Photovoltaic energy generation systems» (Periodic inspection, acceptance inspection according to Art. 35 NIV); ESTI communication No. 2020-0601 on inspection periods; Low-Voltage Installation Ordinance (NIV, SR 734.27) with appendix; empirical values from the installation practice of ecoEn GmbH, Zurich region. The applicable regulations and the guidelines of your grid operator are decisive.
Last updated: 9 July 2026 · Author: ecoEn editorial team
