What is BS EN IEC 61643‑331 about ?
BS EN IEC 61643‑331 is the 331st of components for low-voltage surge protection in multi-series.
BS EN IEC 61643‑331 is a test specification for metal oxide varistors (MOV), which are used for applications up to 1 000 V AC or 1 500 V DC in power lines, telecommunication, or signalling circuits. They are designed to protect apparatus or personnel, or both, from high transient voltages.
Note: BS EN IEC 61643‑331 applies to MOVs having two electrodes and hybrid surge protection Components.
Note: BS EN IEC 61643‑331 also does not apply to mountings and their effect on the MOV’s characteristics. Characteristics given apply solely to the MOV mounted only in the ways described for the tests.
Who is BS EN IEC 61643‑331 for ?
BS EN IEC 61643‑331 on components for low-voltage surge protection is useful for:
- Manufacturer of surge protector
- Manufacturer of electronic equipment
- Electrician
- Research and development
Why should you use BS EN IEC 61643‑331 ?
A surge protective device (SPD) is designed to protect electrical systems and equipment by limiting transient voltages and diverting surge currents. 
BS EN IEC 61643‑331 will help you in classifying the mechanical characteristics that include robustness termination, solderability and marking of surge protection devices. Some failures and defects are detected which can be reduced with the help of BS EN IEC 61643‑331, which gives result in better quality devices.
This electrostatic discharge helps in absorbing impulsive energy for metal oxide varistors (MOV) test and helps in evaluating thermally protected metal oxide varistors (MOV). This BS EN IEC 61643‑331 helps in measuring the parameters of a MOV for purpose of component selection and also helps in verifying the Maximum Continuous Operating Voltage rating of the varistor.
Buying BS EN IEC 61643‑331 will help you in classifying the mechanical and electrical characteristics. These characteristics will help in designing the surge protection components and evaluating the performance of metal oxide varistors (MOV) by limiting the transient voltage.
What’s changed since the last update ?
BS EN IEC 61643‑331:2020 supersedes BS EN IEC 61643‑331:2018. BS EN IEC 61643‑331:2020 includes some technical changes concerning BS EN IEC 61643‑331:2018. These include:
- Varistor MCOV rating assurance test
- An energy rating test (2ms)
- Revised Dielectric strength and insulation resistance tests
