ISO 16750 Climatic Testing

ISO 16750-4 Road Vehicle Compliance Testing for Electronic and Electrical Equipment – Climatic Loads

ISO 16750 evaluates the integrity of electronic and electrical equipment mounted to road vehicles. As an ISO-17025 accredited environmental test lab, Keystone Compliance realizes the importance of climatic load compliance testing. Meeting the environmental test requirements can be difficult. We understand the challenges and guide companies through the process.

Keystone’s engineers take a consultative approach throughout the entire test program. Our accurate test reports are delivered quickly. We proudly provide the peace of mind that all of your needs will be met all under one roof.

Request a quote to see why so many companies partner with Keystone Compliance. Contact us to receive more information on ISO 16750-4 climatic load environmental testing.

Summary of ISO 16750 Part 4 Road Vehicle Electrical Equipment Testing

ISO 16750 applies to electrical and electronic equipment for road vehicles. More specifically, ISO 16750-4 evaluates potential climatic stresses. The standard specifies tests and requirements recommended for the specific mounting location on/in the road vehicle.

Applicable operating temperatures are chosen and given in the specification of the device under testing.

ISO 16750 Testing

Tests at Constant Temperatures

Low-Temperature Tests – This type of test simulates equipment exposure to low temperatures without electrical operation. An example of this would include units being subjected to low temperatures during shipment of the system or component.

This test is performed by IEC 60068-2-1. Method A carries out testing at a temperature of -40 C for 24 hours.

High-Temperature Tests – High-temperature testing simulates exposure to high temperatures without electrical operation. Similar to the low-temperature test, equipment can encounter high temperatures during shipment and transportation. This leads to the warping of the plastic housing.

It is recommended to test the unit to IEC 60068-2-2, Test B. The IEC 68-2-2 test is conducted for 48 hours at a temperature of 85 C.

Temperature Step Test

The ISO 16750-4 temperature step test checks the device for malfunctions that occur within a small section of the operating temperature range.

First, the unit is installed in a temperature chamber. The temperature is decreased in steps of 5 C from 20 C to Tmin (minimum operating temperature). Next, the temperature is increased in steps of 5 C from Tmin to Tmax (the maximum operating temperature).

Temperature Cycling Tests

Temperature cycling stimulates varying temperatures with electrical operation. Temperature cycling can be found when the system is being used at changing ambient temperatures.

The temperature cycling test is performed by IEC 60068-2-14. For this procedure, the temperature of the chamber is raised from Tmin (minimum operating temperature) to Tmax (the maximum operating temperature) within 30 seconds. A soak time is determined. The unit is kept in this soak time after thermal stability is obtained. This time can vary from 20 minutes to 90 minutes.

If a system/component is exposed to hot-soak temperatures, an additional short temperature peak is added during the high-temperature phase of the profile. This will ensure proper functioning during short temperature peaks.

Electrical operation is switched off during phases of decreasing temperature to avoid electrical heat dissipation.

Ice Water Shock Test

ISO 16750-4 ice water shock testing simulates thermal shock induced by water. The test applies to products in the splash areas of a vehicle. Splashing over a hot system/component occurs when driving on wet roads during the winter. A failure is defined as the mechanical cracking of materials. A failure may also occur when a seal fails due to different temperature expansion coefficients.

Splash Water Test – For this test, the unit under testing is heated for a specified time. The unit is then splashed with ice water for 3 seconds.

If the unit is splashed in the vehicle from only one direction, it is splashed only from the specified direction. If the unit is splashed from various directions, these directions are taken to account. A new unit is used for each direction.

Submersion Test – First, the unit under testing is connected to the test equipment. The unit is then operated in a hot air oven. With the device still operating, the unit is submerged in ice water for 5mm. The depth of the tank must be at least 10mm.

Salt Spray Test

This test checks the resistance of materials and surface coatings to salt mist and salt water. Salt mist and salt water can be found on the streets during winter. The test provides corrosion similar to that found during the unit’s life cycle.

Salt spray testing is performed by IEC 60068-2-52. No changes are allowed to impair the normal performance of the unit. If this occurs, the unit is considered to have failed the salt spray test.

Humid Heat Cyclic Test

It is not uncommon for equipment to be subjected to cyclic high ambient humidity. Failure modes addressed are electrical malfunctions caused by moisture. E.g. leakage current caused by a printed circuit board that is soaked with moisture.

Damp Heat Cyclic Test – This procedure is performed to IEC 60068-2-30. The test carries out at an upper temperature of 55C. Six cycles are performed.

Composite Temperature/Humidity Cyclic Test – The test is conducted to IEC 60068-2-38. A functional test is then performed once the maximum cycle temperature is reached.

Dewing Test – This cyclic test is performed by IEC 60068-2-30. The unit is exposed to an upper temperature of 80 C. Five cycles are performed.

Damp Heat Steady-State Test

This ISO 16750-4 test type simulates the use of equipment under steady high ambient humidity. Similar to humid heat cyclic testing, failures are when an electrical malfunction caused by moisture occurs.

Steady stare humidity testing is performed to IEC 60068-2-78. The test lasts 21 days. It has a severity of 40 C and 85% humidity.

Dust Test

Dust testing simulates a dust pumping effect. The effect is caused by temperature changes inside the housing of the unit under testing, due to intermittent electrical operation.

Dust testing is performed according to ISO 20653. Testing is carried out oriented as mounted in the vehicle. Furthermore, the dust test consists of 20 cycles.

Expert ISO 16750 Part 4 Regulatory Compliance Testing

In addition to ISO 16750-4 environmental testing, Keystone has a full scope of expertise including EMC/EMI, shielding effectiveness, and package testing. Keystone has a full lab of test equipment which permits us to provide short lead times on scheduling.

Ready to get started? We are. Contact us to see why so many companies work with Keystone each year to achieve their environmental standard test needs.

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