· SH Energy editorial
The NRS 097 series is part of the South African framework referenced when a small-scale embedded generation system is connected to a distribution network. Whether a particular unit is acceptable at a particular site is decided by the distributor that supplies it, against that distributor’s current conditions. Your job as a buyer is to establish what the supplier can actually evidence for the exact model you are ordering.
1. Why the standard is referenced at all
Embedded generation changes how a site behaves during a grid outage and how it interacts with the network. Interconnection requirements exist so that the network operator can be confident the inverter will disconnect when it should, will not energise a dead network, and will operate within agreed limits. The NRS 097 series is the national reference point in that framework; the municipal resource portal at sseg.org.za publishes the municipal guidance, process and application material around it.
Two things follow. First, the standard is a document you can obtain and cite, so a supplier's answer can be checked against it. Second, the technical conditions can differ between distributors, so a general statement of compliance is not the same as acceptance at a specific site.
2. Ask which model, which document, which version
A compliance claim that is not tied to a model number is unverifiable. Ask for the document that names the model in the unit you are buying, and check that the document is current for the hardware and firmware revision being delivered.
- Which exact model and hardware revision does the document cover?
- Does the document name the model, or only a product family?
- Which edition of the standard does it reference, and is that edition still the one the distributor applies?
- Is the document a third-party test report, a certificate of conformity, or a manufacturer's self-declaration? These are not equivalent.
3. Ask about anti-islanding and protection behaviour specifically
The behaviours that matter most in an interconnection review are the ones that protect the network and the people working on it. Ask how the unit detects loss of grid, how quickly it disconnects, and what it does when the grid returns. Ask whether those settings are fixed at the factory or configurable, and if configurable, who is permitted to change them and how the change is recorded.
A supplier who can answer these questions precisely is usually a supplier who has actually been through an interconnection review. A supplier who answers only with a logo and a slogan has not.
4. Ask what happens when the model changes
Substitution is where compliance quietly breaks. If the delivered model differs from the approved or documented one, the paperwork no longer describes the installation. Ask in writing what happens if the ordered model is unavailable: whether a substitute is offered, whether it carries its own documents, and whether the installer must resubmit anything to the distributor.
Get the answer before the order, not after the container arrives. A substitution discovered at commissioning is a project delay, and in some cases a rejected installation.
5. What a supplier can and cannot honestly provide
A supplier can provide the datasheet naming the exact model, the test report or certificate it holds, interface and protection information, and the operating limits of the unit. That is the technical input to an application.
A supplier cannot decide whether a municipality accepts a model, cannot register the installation, and cannot sign the installer's declaration. Treat any statement that a product “is approved for South Africa” without a model-level document as marketing rather than evidence. The same discipline applies to claims about local support, spare parts and warranty service: ask where the stock is, who performs the repair, and what the response commitment is in writing.
6. Put the answers in the purchase file
Keep the model-level documents with the order, and keep them with the installation record. When the distributor asks which inverter was approved and which one is on site a year later, that file is the answer. It also protects you if the supplier's product line changes and a future service visit needs the same revision.
Copy-ready questions to send a supplier
Does SH Energy hold NRS certification for its models?
Do not assume so. Any statement about standards compliance, listed equipment or approval must be confirmed at exact model level with documents for the specific unit. Ask for the report or certificate that names the model, and confirm acceptability with the distributor who supplies the site.
Is a manufacturer self-declaration the same as a test report?
No. They are different classes of evidence. A self-declaration states the manufacturer's position; a third-party test report records independent measurement. Ask which one you are being given, and read who issued it.
Can the same inverter be accepted by every municipality?
Not necessarily. The technical conditions and the application process sit with the distributor, and they change over time. A unit that is acceptable in one area may need additional information in another, so confirm with the distributor for the actual site.
What if the ordered model is unavailable at shipment?
Ask the substitution policy in writing before ordering. If a different model is delivered, its own documents must exist and the installer may need to update the submitted application.
Discuss a sourcing or sizing enquiry
Send your proposed configuration, the load list you measured and the documents you already hold to jimmy@sunhongenergy.com, or contact Jimmy on WhatsApp. Related reading: the battery storage RFQ checklist, the battery and inverter compatibility checklist and our quality and documents page.
Sources and scope
Reviewed 23 October 2026. Primary reference point: the municipal small-scale embedded generation resource portal at sseg.org.za, managed by Sustainable Energy Africa with SALGA and partners, which publishes municipal guidance, process, tariffs and application material, together with technical standards references and single-line diagram and metering guidance. The NRS 097 series is described here only as the national reference in the interconnection framework; no clause, threshold, disconnect time, protection setting or acceptance outcome is asserted, because those sit with the published standard and with each distributor's current conditions. No model is claimed to be certified, listed, approved or accepted. This is a procurement checklist for buyers and installers, not electrical, legal or municipal advice.