IEC 60335-1: How the General Electrical Safety Standard Works With Gas Appliance Standards

What IEC 60335-1 Covers

• Protection against access to live parts and against electric shock;
• Input power and current, heating and temperature limits in normal use;
• Leakage current and electric strength (dielectric withstand / hipot) at the test temperature;
• Moisture resistance, insulation resistance and electric strength after a damp treatment;
• Overload of transformers and associated circuits, stability and mechanical hazards, mechanical strength;
• Construction, internal wiring, components, supply connection and external flexible cords;
• Terminals for external conductors, protective earthing, screws and joints, creepage distances and clearances;
• Resistance to heat and fire, resistance to rusting, and abnormal operation tests.

These are written as clauses within Part 1; the Part 2 standard states which clauses apply, which are modified, and which additional tests are required. Where Part 1 and Part 2 differ, Part 2 takes precedence.

Part 1 and Part 2: How They Fit

A common error is testing to IEC 60335-1 alone and assuming the appliance is certified. Part 1 alone is not sufficient; the applicable Part 2 and the gas standard must also be covered.

The Core Electrical Tests

The exact test voltages and leakage limits are read from the standard’s tables for the relevant insulation class; they should not be quoted from memory or copied from a different appliance.

Class I vs Class II

• Class I: protection relies on basic insulation plus a protective earth conductor; metal gas and water components are bonded to earth, and the multi-station-qc-upgrade-integrated-stove-plant/" title="Production Line">production line must test earth continuity.
• Class II: protection relies on double or reinforced insulation with no protective earth; the appliance is marked accordingly and insulation/hipot requirements are more demanding.
• Class III: supplied at safety extra-low voltage (SELV); less common for high-power gas appliances.

Division of Labour Between the Standards

An electrical component fitted to a gas appliance (ignition module, fan, controller, solenoid) must satisfy both worlds: it must function safely in the combustion test and meet the electrical-safety requirements in the IEC test.

Where This Sits in CE Marking

• Gas appliances placed on the EU market fall under the Gas Appliances Regulation (EU) 2016/426; the electrical risks are addressed within that assessment using the IEC 60335 series rather than a separate CE mark.
• Appliances outside the gas regulation may use the Low Voltage Directive 2014/35/EU and EMC Directive; the exact route depends on the product.
• The test reports and Declarations of Conformity are kept in the technical file, which is the evidence a market-surveillance authority will request.

On the Production Line

Type-test certification proves the design; the factory must also confirm that every unit is electrically safe. A production electrical-safety station typically performs a quick earth-continuity, hipot (and, where required, insulation/leakage) check in seconds, locks the line if a unit fails, and logs the result against the serial number. This is the “routine test” counterpart to the type tests and is covered in detail in the K cluster. Wanhe can integrate the electrical-safety station with the gas performance bench so a cooker passes both gas and electrical checks and a single serial-numbered record covers both.

How to Navigate the Standard

IEC 60335-1 is organised into numbered clauses that follow the logic of a safety assessment, rather than grouped by component. Early clauses cover definitions, general test conditions and classification; the middle clauses work through the hazards (input, heating, leakage, moisture, transformers, stability, mechanical strength, abnormal operation); and the later clauses cover construction and connections (wiring, components, cords, terminals, earthing, screws) and finally creepage distances, heat/fire resistance and rusting. The annexes add supporting material such as the routine (production-line) test guidance, measurement circuits and explanatory notes. When reading it for a gas appliance, always read each clause through the lens of Part 2-102, which explicitly says “this clause does not apply”, “this clause is modified as follows” or adds an extra test. Engineers who read Part 1 without applying those Part 2 modifications routinely run the wrong test or apply a limit that does not exist for their product. Keep Part 1, Part 2-102 and the gas standard open together so the test plan and the conformity file agree from the first prototype onward.

Common Mistakes

• Testing to IEC 60335-1 without the applicable Part 2 (2-102);
• Assuming the gas standard covers the electrical risks (it does not);
• Using hipot voltages or leakage limits from another product class;
• Forgetting earth-continuity on Class I production units;
• Keeping type-test reports but running no routine electrical tests on the line;
• Applying separate CE marks for risks that should be covered within the Gas Appliances Regulation.