GB/T 1094.11-2022 vs IEC 60076-11:2018 — Key Differences for Dry-Type Transformers

Sample page — GB↔IEC Standards Clause Advisory. Compiled 2026-10-30 from the public sources listed at the end of this page. Clause numbers and key points only — this page does not reproduce standard text.

Introduction

GB/T 1094.11-2022 is China's national standard for dry-type power transformers. It is a modified adoption (MOD) of IEC 60076-11:2018 — published 2022-03-09, in force since 2022-10-01, replacing the 2007 edition. "Modified adoption" is the important part: the Chinese text follows the IEC structure, but it is not a translation, and a transformer built and tested to GB/T 1094.11 is not automatically a transformer built and tested to IEC 60076-11.

This matters in three everyday situations: an overseas buyer checking a Chinese supplier's test report against an IEC-based specification; a Chinese manufacturer adapting a GB design to an IEC tender; and anyone pricing the paperwork in between. An English translation of GB/T 1094.11-2022 alone lists at US$720–1,159 depending on the vendor, with delivery in about a week — and a translation still does not tell you which clauses diverge from IEC or what that means for your product.

Below are the five differences we have verified against public sources, each with its source. Where the two standards actually agree, we say so — see "Where the two agree".

The five verified differences

#	Topic	GB/T 1094.11-2022 (China)	IEC 60076-11:2018	What it means in practice
1	Losses, impedance and sound level are prescribed values in China	GB/T 1094.11 is applied together with its companion standard GB/T 10228-2023, which prescribes — per voltage class (6 / 10 / 20 / 35 kV) and rating — the voltage combinations, connection symbols, no-load loss, load loss, no-load current and short-circuit impedance (clauses 4.1–4.3), and caps the sound level via JB/T 10088 (clause 5.2). China's mandatory GB 20052 additionally sets energy-efficiency limits and grades.	IEC 60076-11 contains no prescribed loss values, no impedance table and no sound-level limits. Losses and impedance are values declared/guaranteed for the specific order; sound level is a special test performed when specified, against a value set by agreement.	A Chinese catalogue rating ("SCB13-1000/10") already embeds fixed loss and impedance numbers from GB/T 10228 and an efficiency grade from GB 20052. An IEC datasheet embeds none of these. Comparing the two without converting is comparing a regulated value against a negotiated one.
2	Insulation levels follow a Chinese table — including a U_m 40.5 kV class	GB/T 1094.11 keeps its own insulation-level table (Table 3), and the dielectric requirements resolve through GB/T 1094.3-2017, itself a modified adoption of IEC 60076-3:2013. The Chinese 35 kV system class is U_m 40.5 kV (the class the GB/T 10228-2023 parameter tables are built around).	Clause 11 of IEC 60076-11:2018 gives two insulation-level tables — one based on European practice and one based on North American practice. There is no 40.5 kV class in the IEC tables.	For the same nominal voltage, the lightning-impulse and power-frequency test levels are selected from different tables and are not interchangeable. A "35 kV class, IEC" claim does not describe a GB 35 kV (U_m 40.5 kV) design, and a GB test certificate does not by itself evidence the IEC dielectric levels.
3	The normative reference chain resolves to Chinese editions, several of them modified adoptions	The standards GB/T 1094.11-2022 actually invokes are Chinese documents: insulation levels per GB/T 1094.3-2017 (MOD of IEC 60076-3:2013), short-circuit withstand per GB/T 1094.5-2008 (MOD of IEC 60076-5:2006), partial-discharge measurement per GB/T 7354-2018 (MOD of IEC 60270), thermal classification per GB/T 11021-2014 (IDT IEC 60085), enclosure protection per GB/T 4208-2017 (IDT IEC 60529:2013). The standard even carries a dedicated annex (Annex B) listing its technical deviations from IEC 60076-11:2018 and their justifications.	IEC 60076-11 invokes the IEC originals of the same parts.	Where the referenced GB part is a modified adoption, its procedures or values can differ from the IEC original. A test report "to IEC 60076-3" does not automatically evidence the corresponding GB clause — the chain has to be checked part by part, which is exactly the check most cross-border spec reviews skip.
4	Seismic qualification is anchored to China's seismic-environment standards	Seismic performance sits in GB clause 13 with a dedicated Annex E (tables E.1–E.4), and the environmental conditions and test guidance are tied to Chinese documents — GB/T 4797.7-2008 (earthquake environmental conditions, IDT IEC 60721-2-6) and GB/T 2424.25 (seismic test guidance).	IEC 60076-11:2018 also has seismic requirements (clause 13, with its own acceleration tables), worked from the IEC 60068-3-3 test-guidance line directly.	Both systems test seismic performance, but the class designations and the test evidence are produced under different document chains. A seismic classification or test report from one system does not map one-to-one onto the other — it has to be re-expressed, and sometimes re-tested.
5	Amorphous-core dry-type transformers have their own Chinese parameter standard	Chinese certification practice applies GB/T 22072-2018 (technical parameters and requirements for dry-type amorphous-alloy core distribution transformers) alongside GB/T 1094.11-2022 — CQC's certification basis lists GB/T 1094.11-2022, GB/T 10228-2023 and GB/T 22072-2018 together. Loss guarantees for Chinese amorphous units are set by these tables (and GB 20052 grades), not by Part 11 alone.	IEC 60076-11:2018 has no companion parameter standard. It covers amorphous cores inside Part 11 itself — recommendations in the foreword and a dedicated special test for amorphous-core transformers (clause 14.4.8).	If you are sourcing or specifying an amorphous-core dry-type unit from China, the numbers that govern it live in GB/T 22072 and GB 20052. Nothing in IEC 60076-11 will tell you whether the unit meets them.

Where the two agree (so you don't pay anyone to "fix" these)

Scope. Both apply to dry-type transformers with highest voltage for equipment up to 72.5 kV and at least one winding above 1.1 kV, with near-identical exclusion lists. (The 72.5 kV ceiling itself was new in the 2022 GB edition — the 2007 edition stopped at 40.5 kV — and brings GB into line with the 2018 IEC revision.)
Temperature-rise limits. Both use the same Table 2 structure — e.g. an average winding temperature rise of 100 K for the 155 (F) insulation system.
Partial discharge. Both systems work to a 10 pC acceptance level for the partial-discharge test.

The differences are real, but they are concentrated in the areas above — prescribed parameter values, dielectric tables, the reference chain, seismic anchoring, and the amorphous-core layer — not spread evenly across every clause.

Typical use cases

Buyer / EPC reviewing a Chinese test report. Your specification says IEC 60076-11; the supplier's type-test report says GB/T 1094.11-2022. Which line items transfer, which need re-testing, and which (losses, impedance, sound) were never IEC values to begin with?
Chinese manufacturer bidding an IEC tender. Your existing design is a GB 35 kV class unit. What changes — dielectric levels, rating plate, guaranteed values — before you can honestly sign an IEC 60076-11 compliance statement?
Importer preparing for the Chinese market. Part 11 is only the top layer. GB/T 10228, GB 20052 (and GB/T 22072 for amorphous units) decide whether the product can actually be sold and labelled in China.
Spec writer checking an "equivalent to IEC" claim. Supplier brochures routinely print "GB/T 1094.11 (IEC 60076-11)". The claim is roughly right structurally and wrong in the specific places listed above — the places that decide acceptance tests.

Paid advisory — GB↔IEC Clause Advisory Desk

This sample page covers one standard pair, at summary level. The paid service goes to clause level, for your specific product and questions:

Per standard (e.g. GB/T 1094.11, GB/T 1094.3, GB/T 1094.7, or another part of the GB/T 1094 series): a complete GB↔IEC key-difference table for that standard, plus written clause Q&A on the questions you submit.
Price: US$149–299 per standard, fixed and quoted before we start, depending on the number of clauses/questions in scope.
Contact: email zyouzhi04@gmail.com · WhatsApp +86 182 5438 3069. Send the standard number and your questions; you will get a fixed quote and delivery time first.

Boundaries, stated plainly: we sell our own original comparison and explanation work. We do not sell, supply or translate standard full texts — buy those from the official channels. This is technical information and interpretation support; it is not certification, and we cannot and do not promise any certification, test or approval outcome.

Sources

All sources accessed 2026-10-30. Standards themselves are copyrighted documents; this page cites clause numbers and key points only.

National Standards Platform of China (SAMR) — GB/T 1094.11-2022 record: modified adoption of IEC 60076-11:2018, published 2022-03-09, implemented 2022-10-01. std.samr.gov.cn
National Standards Platform of China (SAMR) — GB/T 10228-2023 background note: GB/T 1094.11 and GB/T 10228 described as the two basic product standards for dry-type transformers in China, with GB/T 10228 supplementing performance parameters, design and structure requirements for Chinese conditions. std.samr.gov.cn
Code of China — GB/T 1094.11-2022 (English version) page: scope text, full table of contents (incl. Annex B "Technical Deviations between This Document and IEC 60076-11:2018 and Their Justifications", Annex E seismic tables) and the normative reference list. English translation listed at US$720. codeofchina.com
IEC Webstore — IEC 60076-11:2018 product page: scope, and the official list of main changes vs the 2004 edition (scope extension to 72.5 kV, new climatic classes, fire behaviour classes limited at 1,000 kVA, introduction of seismic class, recommendations for amorphous transformers). webstore.iec.ch
iTeh Standards — IEC 60076-11:2018 RLV table of contents: separate insulation-level tables "based on European practice" / "based on North American practice"; clause 13 seismic; clause 14.4.8 special test for amorphous-core transformers. standards.iteh.ai
China Quality Certification Centre (CQC) — notice on transformer safety certification under the new standard editions, 2023-08-29: certification basis lists GB/T 1094.3-2017, GB/T 1094.11-2022, GB/T 10228-2023 and GB/T 22072-2018 together. cqc.com.cn
GB/T 10228-2023, English-edition excerpt: clause 4.1–4.3 prescribed parameter tables for 6/10/20/35 kV classes; clause 5.2 sound level per JB/T 10088. sohu.com
Daqo Group — amorphous dry-type transformer product page, showing the standards stack applied in practice on a Chinese datasheet: GB 20052-2024, GB/T 22072-2018, GB/T 1094.11-2022. daqo.com
Chinese Standard Net — GB/T 1094.11 English-edition listing: 2022 edition at US$1,159 with 7-day delivery (translation only, no interpretation). chinesestandard.net