Do resistors need to go through safety regulations?

In the field of electronic components, the safety of resistors as basic components is directly related to the reliability of end products. Regarding whether resistors need to pass safety regulations and which product applications require resistor over safety regulations, professional analysis should be conducted from the following perspectives.
1、 The core value of resistance safety certification
Safety certification (such as UL, IEC, CSA, etc.) is a safety performance evaluation system for electronic components and terminal products. For resistors, safety certification mainly verifies their voltage resistance, flame retardancy, temperature rise characteristics, and environmental adaptability, ensuring that they will not cause safety hazards such as fire and electric shock under extreme conditions (such as overload, short circuit, high temperature).
2、 Application scenarios for products that require resistance over safety regulations
The following product categories have mandatory requirements for the safety performance of resistors due to their involvement in personal safety or high-risk environments:
1. In the field of consumer electronics
Application scenarios: chargers, power adapters, laptops, smartphones, etc.
Safety requirements:
Voltage withstand test: It is necessary to pass the AC 3000V or above voltage withstand test to ensure insulation performance.
Temperature rise control: During full load operation, the surface temperature rise of the resistor should be below 75K to avoid the risk of burns.
Flame retardant rating: Must comply with UL94 V-0 flame retardant standard to prevent the spread of fire.
2. Industrial control field
Application scenarios: PLC (Programmable Logic Controller), servo drives, industrial robots, etc.
Safety requirements:
Anti vibration and shock: It is necessary to pass the IEC 60068-2-6 vibration test to ensure the stability of resistance parameters under mechanical shock.
Moisture and dust prevention: IP67 level protection to prevent deterioration of resistance performance in humid environments.
Overload capacity: It needs to withstand 3 times the rated power impact for 5 seconds and adapt to sudden loads in industrial sites.
3. In the field of new energy vehicles
Application scenarios: Battery Management System (BMS), Motor Controller, OBC (On Board Charger), etc.
Safety requirements:
High temperature tolerance: It needs to undergo temperature cycling testing from -40 ℃ to+155 ℃ to adapt to extreme weather conditions.
Gas corrosion protection: Meets ISO 16750-4 sulfurization gas testing to prevent resistance layer detachment.
Electromagnetic compatibility: CISPR 25 electromagnetic radiation test is required to prevent interference with onboard electronic systems.
4. Medical equipment field
Application scenarios: life support equipment (such as ventilators), imaging diagnostic equipment (such as CT machines), wearable medical devices, etc.
Safety requirements:
Biocompatibility: Must pass ISO 10993-1 testing to avoid heavy metal precipitation.
Leakage current control: In humid environments, the leakage current should be below 10 μ A to ensure patient safety.
Cleanliness and disinfection tolerance: It needs to withstand more than 1000 alcohol wipes to meet the disinfection requirements of medical environments.
5. Aerospace field
Application scenarios: satellite power systems, onboard electronic equipment, rocket propulsion control modules, etc.
Safety requirements:
Radiation tolerance: Total dose radiation testing (TID) is required to ensure stable performance in space radiation environments.
Vacuum discharge protection: It must meet the MIL-STD-883 vacuum discharge test standard to avoid electrostatic breakdown.
Thermal cycle reliability: It needs to pass a rapid temperature change test from -55 ℃ to+125 ℃ to adapt to extreme temperature differences in space.
3、 Selection suggestions and industry trends
Prioritize certification models such as Vishay's RCWE series (UL certified) and Yageo's PRT series (IEC certified) to shorten the product certification cycle.
Pay attention to emerging standards, such as the EU RoHS 3.0 restrictions on flame retardants, and choose halogen-free resistors.
Customization requirements: In the aerospace field, resistors that meet MIL-PRF-55342 military standards need to be selected.
With the development of electronic devices towards high power density and high reliability, safety certification of resistors has become a necessary condition for product market access. When selecting, engineers need to consider the security level of the application scenario, balance performance, cost, and certification cycle to build a safe and efficient electronic system.