Answer: what NRS 097-2-1 means for a solar project
NRS 097-2-1 specifies the utility interface for small-scale embedded generation operating in parallel with South Africa’s electricity network. It addresses compatibility, protection and metering. Check the exact inverter evidence and edition, the installation requirements and the electricity distributor’s approval process separately. An equipment certificate does not authorize an installation or guarantee permission to connect.
This guide is for South African installers and designers. Primary documents were checked on 30 September 2026. It explains document review and responsibilities; it does not prescribe project-specific settings or certify an installation.
Identify the specification and its scope correctly
The published NRS 097-2-1:2024 Edition 3 document identifies itself as a user specification issued by Eskom’s Technical Governance Department on behalf of the user group. It explicitly distinguishes itself from a South African National Standard. SABS involvement in standards does not make every NRS document a SANS.
Its focus is the AC utility interface of parallel generation, including relevant storage configurations. Review the actual system topology: a product described as “hybrid,” “off-grid” or “zero export” does not by itself establish which rules apply.
Use the reviewed edition as an identified reference, and confirm any later revision and operator requirements for the application date. This review does not establish that no newer document exists or certify every municipality’s adoption policy.
Separate four kinds of evidence
| Evidence | What it supports | What it does not establish by itself |
|---|---|---|
| Inverter type-test certificate | Tested equipment, scope, edition and applicable conditions | Correct installation of the whole project |
| Operator-recognized equipment listing | Acceptance under that operator’s stated verification route | A universally approved brand or every model in a family |
| CoC and installation/commissioning records | Required installation checks and responsible sign-off | Every separate connection or tariff approval |
| Distributor authorization and agreements | Permission and conditions under the actual connection process | An exemption from maintaining the installation safely |
These records should agree on equipment, configuration and site. A supplier’s “NRS compliant” brochure is not an adequate replacement for the evidence required by the distributor.
Verify the exact inverter and certificate
Before placing an order, create an equipment evidence register. Keep:
- Full model identifier and relevant hardware/firmware configuration.
- Certificate number, issuing body and supporting test-report reference.
- Tested NRS edition and scope, not just the letters “NRS.”
- Ratings and any external protection or configuration conditions.
- Applicable validity or withdrawal conditions.
- The operator’s listing or written acceptance reference and date checked.
A safety certificate to IEC 62109 addresses a different question from NRS interface testing. Do not substitute one for the complete evidence requested in the connection process.
Eskom’s current EGI form provides two evidence routes
The EGI report linked from Eskom’s current SSEG page distinguishes a model on the latest approved City of Cape Town list from independent accredited third-party type-test certification. Its listed-model route does not require a separate certificate attachment; the independent route does. Eskom says it does not approve inverter brands.
Check the exact route and current form. A model missing from the Cape Town list is not automatically unacceptable under every Eskom application; conversely, a brand appearing on a list is not approval of every variant.
For municipal projects, use that municipality’s actual requirements. Cape Town’s official application page links its equipment list and authorization instructions. Obtain the list through that page to avoid relying on an old cached copy.
Protection settings: read the edition, not a remembered shortcut
Protection limits include a response time and operating conditions. Treating a frequency number alone as a commissioning instruction can produce the wrong result.
For example, Table 3 of the reviewed 2024 edition specifies under-frequency below 47 Hz with a maximum trip time of 0.2 seconds, and over-frequency above 51.5 Hz with a maximum trip time of 4 seconds. This is different from a blanket “47.5 Hz / 51.5 Hz, both 10 cycles” rule. Voltage protection is also staged; the table cannot be reduced to one under-voltage and one over-voltage percentage.
These examples explain why to consult the actual table. They are not a complete settings schedule: read the associated notes, tolerances, grid-code precedence, equipment instructions and distributor conditions. Have the appropriately qualified responsible person establish and verify the applicable configuration.
Access controls are a safeguard
Do not unlock, bypass or adjust a protected setting merely because a generic article says to “configure NRS values.” Password protection can be intentional. Record the authorized grid profile, relevant settings evidence and commissioning method. Ask the manufacturer or distributor how to verify an approved configuration when direct adjustment is restricted.
A factory profile may be correct or incorrect for the proposed installation. Verify it rather than assuming all factory defaults fail or all “South Africa” selections are sufficient.
Anti-islanding and backup are different functions
Unintentional islanding means generation continues energizing a portion of the utility network after it has become isolated. An intentional backup island supplies designated customer loads after separation from the utility. A backup capability does not authorize backfeeding the disconnected network.
The qualified design review should establish the actual disconnection, backup switching, neutral/earthing arrangement and manufacturer requirements. Check the documented tested combination, not just the presence of a battery or optimizer.
Anti-islanding verification and export-limiter verification should be recorded separately. A limiter aims to control export during normal parallel operation; it is not proof that the system can never energize the utility during a fault.
Power factor and metering need their own review
A datasheet’s available reactive-power range does not establish the required operating profile. Check the applicable clauses, loading conditions, grid-code and operator instructions. Do not use a blanket “0.9 leading to 0.9 lagging” capability claim as the South African operating requirement.
Metering and export compensation also depend on the agreed connection. Confirm the meter, export permission, limiter configuration where applicable, tariff and agreement. Do not equate interface certification with entitlement to export credits.
Eskom’s current SSEG guidance explicitly addresses registration of relevant non-exporting systems. Fully independent configurations have a different evidentiary question; confirm the physical arrangement and applicable declaration requirements rather than calling any zero-export mode “off-grid.”
Signatories and permissions differ by distributor
The electrical installation’s CoC, EGI report and municipal commissioning sign-off are distinct records. Check who is permitted to issue each for the project.
Eskom’s current EGI form identifies Department of Employment and Labour registration categories for its applicable low-voltage report. Cape Town’s process separately requires ECSA professional involvement for its relevant PV/battery application and distinguishes permission to install from authorization to switch on. Do not transfer one operator’s signatory rule to another.
Confirm the document version, applicability, registration category and actual scope before appointing the responsible person. A training badge, supplier course or software-generated report does not establish statutory authority to sign.
Keep NRS 097-2-3 and medium voltage distinct
NRS 097-2-3 addresses simplified utility connection criteria for low-voltage-connected generators. It should not be described as a medium-voltage interface standard.
If the proposed connection is at medium voltage, refer it to the operator’s applicable engineering and connection process. Do not decide the voltage category, relay arrangement or required study from a generic “above 75 kVA” cutoff. Identify the actual point of connection and approved network solution.
A four-step document review and handover
1. Identify the distributor and project route
Confirm the electricity supply authority, connection voltage, total generation configuration and export/backup arrangement. Obtain its current application instructions and identify the applicable technical and signatory requirements.
2. Verify the exact equipment evidence
Match inverter model, ratings and relevant configuration to the accepted listing or type-test evidence required by that operator. Record the certificate reference, tested edition, scope, conditions and the date acceptance was checked.
3. Complete installation and commissioning records
The appropriately registered responsible person should verify the actual installation, authorized settings and required tests. Keep the applicable CoC, installation report, as-built diagram and supporting records consistent; do not substitute supplier claims for completed checks.
4. Complete the operator approval and handover
Submit the required records through the applicable Eskom or municipal process. Resolve conditions, metering and agreements, and retain the authority’s applicable approval before energization. Give the owner the current operating and safety documentation.
Example: an inverter model changes before commissioning
Suppose a supplier replaces the quoted model with a similarly named variant. This is a hypothetical review example, not an approved design. Check whether the certificate or accepted-list entry covers the replacement. Then check ratings, protection/configuration requirements and affected drawings. Update the operator submission where required and retain the decision. A matching brand logo is not enough.
Keep a record of unresolved questions and the person responsible for closing each one. Installation, sign-off and energization should follow the applicable authority process; no approval timeline or fee waiver is promised here.
For the broader process, see the South Africa compliance hub and Eskom SSEG registration guide. When evaluating SurgePV’s solar design workflow, bring the required drawings and forms and check which outputs support your team. Software does not certify the project or replace responsible sign-off.
Frequently asked questions
What does NRS 097-2-1 cover?
It addresses the utility interface of small-scale embedded generation operating in parallel with the network. The reviewed 2024 Edition 3 is an NRS user specification, not a South African National Standard. Equipment evidence, installation compliance and permission to connect remain separate checks.
Is an inverter certificate permission to connect?
No. Match the exact equipment and applicable edition to the operator’s acceptance requirements, then complete the required installation records and connection process. A certificate or accepted equipment listing does not approve the project’s wiring, configuration, metering or energization.
Does zero export remove the need for approval?
Software limiting export does not make a system incapable of parallel operation. Confirm the actual hardware configuration and distributor requirements. Eskom’s current page explicitly requires registration of relevant non-exporting grid-connected systems; a municipal process can have its own conditions.
Does a locked protection menu make an inverter unsuitable?
Not automatically. The reviewed specification requires programmable safety-disconnect parameters to be protected from unauthorized interference. The responsible person should verify the correct approved configuration through the authorized commissioning process rather than bypassing access controls.
Can a 2017 certificate be assumed acceptable for a new installation?
No. The reviewed 2024 specification includes a two-year transition for installation of equipment certified under earlier versions and distinguishes existing approved installations. Verify the applicable publication date, current operator policy and exact certificate before specifying equipment for a new project.
Is NRS 097-2-3 the medium-voltage standard?
No. In the reviewed NRS 097-2-1 foreword, section 2-3 addresses simplified utility connection criteria for low-voltage-connected generators. A medium-voltage connection requires the network operator’s applicable process and technical review; it should not be classified using a generic 75 kVA shortcut.
