How to Perform IEC 62196 Temperature Rise Test for EV Charging Connectors? Full Guide for CCS1, CCS2, Type 1 & Type 2

As EV charging technology continues to evolve toward higher charging power and faster charging speeds, thermal performance has become one of the most critical safety indicators for EV charging connectors.

Whether the connector is used in a residential AC charging station or a high-power DC fast charging network, excessive heating can lead to contact degradation, insulation damage, charging interruptions, and even safety hazards.

To ensure safe operation, IEC 62196 establishes temperature rise requirements for EV charging plugs, sockets, vehicle connectors, vehicle inlets, and charging cable assemblies.

Among all IEC 62196 electrical performance tests, the Temperature Rise Test is considered one of the most important evaluations because it directly reflects the current-carrying capability and thermal reliability of the connector.

This article provides a complete guide to IEC 62196 temperature rise testing, including test principles, applicable standards, test procedures, common failure modes, test equipment requirements, and practical recommendations for CCS1 and CCS2 connector manufacturers.

The IEC 62196 Temperature Rise Test evaluates the thermal behavior of EV charging connectors when carrying their rated current under specified operating conditions.

The objective is to verify that:

• Current-carrying contacts operate within the temperature-rise limits specified by IEC 62196.
• Contact resistance remains stable during operation.
• Connector design is suitable for long-term charging applications.
• User safety and charging reliability are maintained.

Unlike mechanical endurance tests, temperature rise testing focuses on electrical and thermal performance under load.

The test is performed by applying rated current to a fully assembled connector system while continuously monitoring temperatures at critical locations.

The measured temperature rise is calculated as:

Temperature Rise = Measured Temperature − Ambient Temperature

The resulting values are then compared with the limits specified in the applicable edition of IEC 62196.

As charging current increases, even small increases in contact resistance can generate significant heat.

According to Joule's Law:

Heat Generated ∝ I²R

This means that doubling the current can increase heat generation dramatically if contact resistance remains unchanged.

For modern CCS2 DC fast charging connectors carrying several hundred amperes, thermal performance becomes even more important.

Excessive heating may cause:

• Contact deformation
• Spring force reduction
• Connector housing damage
• Insulation degradation
• Charging interruption
• Connector failure
• Reduced product lifespan

For this reason, temperature rise testing is a mandatory evaluation during product development and certification.

Temperature rise testing is commonly associated with:

General requirements for plugs, socket-outlets, vehicle connectors and vehicle inlets.

Requirements for AC charging interfaces including:

• Type 1
• Type 2

Requirements for DC charging interfaces including:

• CCS1
• CCS2

The test requirements vary depending on connector type, rated current, contact configuration, and application.

IEC 62196 temperature rise testing is commonly performed on:

• Type 1 Connectors
• Type 2 Connectors

• CCS1 Connectors
• CCS2 Connectors

• Vehicle Inlets
• Vehicle Connectors
• Charging Plugs
• Charging Sockets
• Charging Cable Assemblies

Both AC and DC charging interfaces require temperature rise evaluation during product qualification.

Provides stable programmable output current.

Records temperatures from multiple measurement points simultaneously.

Typically installed on:

• Current-carrying contacts
• Protective earth contacts
• Cable terminations
• Critical thermal locations

Provides:

• Real-time monitoring
• Temperature trend curves
• Automatic report generation

Protects operators and equipment during high-current testing.

Representative production samples are assembled according to the manufacturer's specifications.

The connector should be installed exactly as intended for actual service conditions.

Thermocouples are attached to locations specified by the test plan.

Common measurement locations include:

• Current contacts
• Protective earth contacts
• Cable terminations
• Connector housing areas

Correct thermocouple placement is critical for obtaining reliable results.

The sample is connected to the high-current test system.

All connections should be secure to prevent additional resistance from influencing the results.

The connector is energized at its rated current.

The actual test current depends on:

• Connector rating
• Connector type
• Standard requirements

The current is maintained until temperatures stabilize.

Temperature stabilization indicates thermal equilibrium has been achieved.

Temperatures are continuously recorded.

Software automatically generates temperature curves and stores test records.

The measured temperature rise is compared with the applicable IEC 62196 requirements.

Connectors exceeding allowable limits are considered non-compliant.

Poor contact quality increases heat generation.

Reduced spring force decreases effective contact area.

Improper crimping creates localized hot spots.

Oxidation increases resistance and heating.

Repeated mating cycles may degrade electrical performance.

Unsuitable conductive materials can reduce thermal performance.

With the rapid adoption of DC fast charging infrastructure, CCS2 connectors are required to handle increasingly higher currents.

Major challenges include:

• Contact heating
• Current density
• Thermal stability
• Long-term reliability

Manufacturers often perform extensive temperature rise testing during product development to optimize:

• Contact geometry
• Plating thickness
• Spring force
• Conductor design

Although both tests involve current flow, their objectives are different.

Purpose:

Evaluate thermal performance under rated operating current.

Focus:

• Contact resistance
• Thermal stability
• Long-term reliability

Purpose:

Evaluate connector performance under high fault current conditions.

Focus:

• Mechanical integrity
• Thermal withstand capability
• Safety performance

Many advanced IEC 62196 test systems can perform both tests using a single platform.

A complete testing solution typically includes:

• Programmable current source
• Temperature acquisition unit
• Thermocouples
• Test fixtures
• Monitoring software
• Safety protection system

For high-power EV connectors, systems with output capability up to 6500A can support:

• Temperature Rise Test
• Short-Time Current Test
• Current Carrying Capability Test
• Protective Earth Circuit Test

To verify that EV charging connectors can carry rated current without exceeding allowable temperature-rise limits.

Yes. All types connectors including CCS2 and Type 2 are among the most common applications.

Temperature at current-carrying contacts, earth contacts, cable terminations, and other specified locations.

Temperature rise testing is an important part of IEC 62196 compliance evaluation.

Many advanced systems support both functions.

The IEC 62196 Temperature Rise Test is one of the most important evaluations for EV charging connector safety, performance, and certification.

By accurately measuring connector thermal behavior under rated current conditions, manufacturers can verify compliance, improve reliability, optimize product design, and reduce certification risks.

For EV connector manufacturers, EVSE manufacturers, automotive laboratories, and certification organizations, a reliable IEC 62196 Temperature Rise and Short-Time Current Test System is essential for validating CCS1, CCS2, Type 1, and Type 2 charging interfaces before market release.