Inverter Reactive-Power Grid-Support Test — CN→AU Corridor (Sungrow SG125HT)

Standard Operating Procedure · Equipment: Sungrow SG125HT three-phase string inverter · Document ID: TVT-SOP-CN-AU-INV-014 · Revision: A · Effective: 2026-09-21

Type: Process / SOP Corridor: CN → AU Site class: B2B / utility-adjacent Owner role: Commissioning Engineer

Verdict: ~6 hours on-site. This SOP executes the volt-var / volt-watt acceptance test of the Sungrow SG125HT three-phase string inverter per AS/NZS 4777.2:2020. Proceed only after firmware, LOTO, and AC source readiness are confirmed.

Equipment: Sungrow SG125HT (1500 V DC, C&I three-phase string inverter) [Src: Sungrow product range | URL: https://www.sungrowpower.com/en/products/string-inverter | accessed 2026-09-21]. Location: CN → AU export corridor, on-site at AU PCC. Horizon: Single visit, Day 1. Evidence date: 2026-09-21.

Item	Value	Source
Equipment model	Sungrow SG125HT (3-phase string inverter)	https://www.sungrowpower.com/en/products/string-inverter
Standard	AS/NZS 4777.2:2020 (clause on grid-support volt-var/volt-watt)	https://www.standards.org.au
Duration	~6 hours on-site (model assumption pending site survey)	Internal estimate
HS code candidate	8504.40 (static converters — to be confirmed by licensed broker)	https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff
Incoterm default	CIF Australian port per Incoterms 2020	https://iccwbo.org/business-solutions/incoterms-rules/incoterms-2020/
Limitation	Specific SG125HT service-manual revision confirmed at RFQ; SOP parameters derived from public datasheet envelope only	Model assumption

1. Purpose and Scope

This SOP governs the on-site acceptance test of the reactive-power (volt-var / volt-watt / Q(V)) grid-support functions of the Sungrow SG125HT three-phase string inverter before hand-over on the China-to-Australia export corridor. It applies to SG125HT units shipped under Tradvolt job numbers prefixed TVT-CAU-. The SG125HT is a 1500 V DC, C&I-rated three-phase string inverter; exact firmware parameter set, clearing time, and tolerance values must be reconfirmed against the current Sungrow SG125HT service manual revision at the time of commissioning.

2. Reference Documents

AS/NZS 4777.2:2020 — Grid connection of energy systems via inverters, Part 2: Inverter requirements (specifically the volt-var (Table 4) and volt-watt (Table 5) clauses for Australia A/B/C regions) [Src: Standards Australia | URL: https://www.standards.org.au | accessed 2026-09-21].
IEC 62109-1:2010 — Safety of power converters for use in photovoltaic power systems [Src: IEC Webstore catalogue query IEC 62109-1 | URL: https://webstore.iec.ch/en/products/?q=62109-1 | accessed 2026-09-21].
IEC 61683:1999 — Photovoltaic systems — Power conditioners — Procedure for measuring efficiency [Src: IEC Webstore catalogue query IEC 61683 | URL: https://webstore.iec.ch/en/products/?q=61683 | accessed 2026-09-21].
Sungrow SG125HT service manual, current regional (AU) revision — title and revision confirmed at RFQ [Src: Sungrow service documentation for SG125HT | URL: https://www.sungrowpower.com/en/products/string-inverter | accessed 2026-09-21].
Sungrow SG125HT datasheet, current regional (AU) revision — title and revision confirmed at RFQ [Src: Sungrow SG125HT datasheet | URL: https://www.sungrowpower.com/en/products/string-inverter | accessed 2026-09-21].
ISO 2859-1:1999 — Sampling procedures for inspection by attributes, General Level II / AQL 1.0 framework [Src: ISO catalogue search "2859" | URL: https://www.iso.org/search.html?q=2859 | accessed 2026-09-21].
Incoterms 2020 — ICC publication 723E, CIF rule A3 / A4 / B3 / B4 [Src: ICC Incoterms 2020 official rules page | URL: https://iccwbo.org/business-solutions/incoterms-rules/incoterms-2020/ | accessed 2026-09-21].
ABF Working Tariff — current tariff-classification page for HS heading 8504.40 [Src: Australian Border Force | URL: https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff | accessed 2026-09-21].
China Customs — General Administration of Customs, export tariff consultation [Src: GACC | URL: http://english.customs.gov.cn | accessed 2026-09-21].

3. Preconditions

Equipment has cleared CN export inspection and AU import biosecurity with no open holds.
DC string and LFP battery DC bus voltage measurements are within Sungrow SG125HT datasheet limits (MPPT voltage envelope and max DC input voltage per the current AU datasheet revision — confirmed at RFQ).
AC grid-forming source is available at the point of common coupling (PCC).
Two qualified Commissioning Engineers are present with calibrated instruments traceable to ISO/IEC 17025.

4. Step Sequence

Step #	Action	Owner	Input doc	Output doc	Done-when
1	Confirm single-line diagram, PCC, and AS/NZS 4777.2:2020 region setting (A/B/C)	Commissioning Engineer	TVT-PRJ-CAU-001 SLD	Pre-test checklist	Region code recorded and signed
2	Lock-out / tag-out DC and AC isolators per Sungrow SG125HT service manual (current AU revision)	Site Safety Officer	LOTO register; Sungrow SG125HT service manual	LOTO permit	Zero-energy verified on calibrated meter
3	Verify SG125HT firmware version matches AU parameter set (region code, volt-var / volt-watt curves)	Commissioning Engineer	Firmware manifest; SG125HT service manual	Firmware sign-off sheet	Hash match logged in commissioning folder
4	Connect programmable AC source ≥110% of SG125HT nominal apparent power	Test Technician	AC source calibration cert	Source connection log	Three-phase voltages balanced ±2%
5	Run volt-var curve through V1–V4 per AS/NZS 4777.2:2020 Table 4	Commissioning Engineer	Volt-var test sheet	Reactive-power CSV	Q output within ±5% of setpoint at each step
6	Run volt-watt curve through Vw1–Vw4 per AS/NZS 4777.2:2020 Table 5	Commissioning Engineer	Volt-watt test sheet	Active-power CSV	P curtailment within ±5% of setpoint at each step
7	Repeat Q(V) three times; compute mean reactive error against SG125HT datasheet tolerance	Test Technician	CSV set; SG125HT datasheet	Repeatability report	Mean error ≤ SG125HT datasheet tolerance band
8	Spot-check anti-islanding: open AC contactor, record clearing time against SG125HT service-manual limit	Commissioning Engineer	Anti-island log; SG125HT service manual	Anti-island record	Trip ≤ SG125HT service-manual clearing time
9	Visual AQL inspection per ISO 2859-1:1999 General Level II, AQL 1.0	QC Inspector	ISO 2859-1 General Level II / AQL 1.0 sampling table	AQL inspection form	Sample defects ≤ accept number
10	Compile evidence pack: PDF report, screenshots, raw CSVs	Documentation Lead	All prior outputs	Final commissioning dossier	Dossier uploaded to job folder, link issued

5. Acceptance Criteria

Reactive-power response within ±5% of programmed curve across the V1–V4 window per AS/NZS 4777.2:2020 Table 4 [Src: Standards Australia — AS/NZS 4777.2:2020 | URL: https://www.standards.org.au | accessed 2026-09-21].
Active-power curtailment within ±5% across the Vw1–Vw4 window per AS/NZS 4777.2:2020 Table 5 [Src: Standards Australia — AS/NZS 4777.2:2020 | URL: https://www.standards.org.au | accessed 2026-09-21].
Anti-islanding clearing time within the interval stated in the Sungrow SG125HT service manual (current AU revision — confirmed at RFQ) [Src: Sungrow SG125HT service manual | URL: https://www.sungrowpower.com/en/products/string-inverter | accessed 2026-09-21].
Efficiency measured per IEC 61683:1999 within Sungrow SG125HT datasheet tolerance band [Src: IEC — IEC 61683:1999 (catalogue query) | URL: https://webstore.iec.ch/en/products/?q=61683 | accessed 2026-09-21].

6. Document Checklist (filenames)

TVT-CAU-PRE-CHECK-001.pdf — pre-test safety checklist
TVT-CAU-LOTO-PERMIT-001.pdf — lock-out / tag-out permit (cites Sungrow SG125HT service-manual revision)
TVT-CAU-FW-SIGNOFF-001.pdf — SG125HT firmware hash and parameter-set sign-off
TVT-CAU-VOLTVAR-CSV.zip — volt-var raw measurement archive
TVT-CAU-VOLTWATT-CSV.zip — volt-watt raw measurement archive
TVT-CAU-REPEAT-REP-001.pdf — repeatability report
TVT-CAU-ANTIISLAND-001.pdf — anti-islanding record
TVT-CAU-AQL-FORM-001.pdf — ISO 2859-1:1999 AQL inspection form (General Level II, AQL 1.0)
TVT-CAU-FINAL-DOSSIER-001.pdf — final commissioning dossier

7. Timeline and Dependencies

Phase	Activity	Dependency	Indicative duration
Pre-arrival	Documentation review and SG125HT firmware staging	Job number issued; Sungrow SG125HT service-manual revision on file	2 working days — UNCERTAIN pending AU customs hold
On-site Day 1 AM	LOTO, AC source connection	PCC energised, safety permits	2 h
On-site Day 1 PM	Volt-var + volt-watt curves	Steps 1–4 closed	2 h
On-site Day 1 PM	Repeatability and anti-islanding	Curve tests signed off	1 h
On-site Day 1 PM	AQL visual + dossier upload	All measurements captured	1 h

8. Cost Indicative Slots

All figures below are indicative and UNCERTAIN; final quotation is issued only after RFQ intake and current carrier/authority tariff lookup on 2026-09-21.

Engineering labour (2 engineers × 1 day) — indicative
AC source rental — indicative
Calibration certificates pass-through — indicative
AU customs entry fee — UNCERTAIN pending ABF schedule at HS 8504.40
CN export inspection fee — UNCERTAIN pending GACC schedule

9. Duty / HS Code Block

Equipment / parts: Sungrow SG125HT three-phase string inverter (1500 V DC, C&I class) with grid-support functions.

Recommended HS code candidate (must be confirmed by a licensed customs broker at booking):

8504.40 — Static converters — typical heading for power inverters on the AU Working Tariff [Src: Australian Border Force — current tariff-classification page for HS 8504.40 | URL: https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff | accessed 2026-09-21].
8504.40.00 sub-line — to be confirmed against the AU Working Tariff and CN Customs Export Tariff at the time of shipment.

Duty rate: PENDING — lookup against the ABF Working Tariff current-tariff section and any applicable Free Trade Agreement (e.g., ChAFTA) preference at the time of entry.

GST / VAT: PENDING — lookup.

Official portals consulted: Australian Border Force current tariff-classification page (https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff) and GACC (http://english.customs.gov.cn).

Disclaimer: HS classification and duty rates are jurisdiction-specific and time-sensitive. Tradvolt does not issue binding tariff rulings; the buyer is responsible for engaging a licensed customs broker and confirming the classification, preferential origin, and applicable rate at the date of export and import.

10. Incoterms Reference

Default quotation basis for this corridor is CIF Australian port per Incoterms 2020 (rule CIF, ICC publication 723E); alternative terms (FOB, DAP, DDP) available on RFQ. Risk transfer and cost allocation follow the official ICC Incoterms 2020 rules page [Src: ICC — Incoterms 2020 | URL: https://iccwbo.org/business-solutions/incoterms-rules/incoterms-2020/ | accessed 2026-09-21].

11. Reader-facing CTAs

Request Quote — replies in 48h

12. Claim Rows

Claim: Volt-var curve is specified by V1–V4 setpoints in AS/NZS 4777.2:2020 (Table 4 referenced under the volt-var clause). [Claim | Src: Standards Australia — AS/NZS 4777.2:2020 | URL: https://www.standards.org.au | accessed 2026-09-21]
Claim: Volt-watt curve is specified by Vw1–Vw4 setpoints in AS/NZS 4777.2:2020 (Table 5 referenced under the volt-watt clause). [Claim | Src: Standards Australia — AS/NZS 4777.2:2020 | URL: https://www.standards.org.au | accessed 2026-09-21]
Claim: Reactive-power tolerance applied on this SOP is ±5% of programmed curve. [Claim | Src: Standards Australia — AS/NZS 4777.2:2020 | URL: https://www.standards.org.au | accessed 2026-09-21]
Claim: AQL sampling is conducted at General Level II, AQL 1.0 per ISO 2859-1:1999. [Claim | Src: ISO — ISO 2859-1:1999 (catalogue search) | URL: https://www.iso.org/search.html?q=2859 | accessed 2026-09-21]
Claim: HS heading 8504.40 is the typical classification for static converters / power inverters on the AU Working Tariff. [Claim | Src: Australian Border Force — current tariff-classification page for HS 8504.40 | URL: https://www.abf.gov.au/importing-exporting-and-manufacturing/tariff-classification/current-tariff | accessed 2026-09-21]
Claim: Incoterms 2020 CIF rule definition follows ICC publication 723E (official Incoterms 2020 rules page). [Claim | Src: ICC — Incoterms 2020 | URL: https://iccwbo.org/business-solutions/incoterms-rules/incoterms-2020/ | accessed 2026-09-21]
Claim: Total on-site procedure duration is approximately six hours including dossier sign-off. [Model assumption | Src: Tradvolt internal estimate, TVT-SOP-CN-AU-INV-014 Rev A | accessed 2026-09-21]
Claim: Sungrow SG125HT is the specific equipment model governed by this SOP; service-manual revision, clearing-time limit, and Q/P tolerance bands are confirmed against the current AU service manual at RFQ. [Model assumption | Src: Sungrow SG125HT product page | URL: https://www.sungrowpower.com/en/products/string-inverter | accessed 2026-09-21]