Surge Filter

Surge Filter each electrical and electronic equipment is in practice exposed to disturbing influences. Disturbance can be classified from different perspectives. Depending on the nature we distinguish: noise, impulse disturbances and transients. In the last decade with the boom in electronics has increased the importance of high frequeny disturbances, which, unlike the low-frequency is easily transmitted, whereas the disturbances ways are harder to define. Electromagnetic compatibility (recompatibility), EMC, is defined as the ability of a device, system or appliance to show the correct operation even in environments, where operate other sources of electromagnetic signals (natural or artificial), while its own "electromagnetic action" does not approach their surroundings, ie. not emit any signals that would disturb other devices.

Disturbance is spreading by means of:

• Galvanic coupling (conductive connection)
• Capacitive and inductive coupling (applied between nearby conductors)
• Electromagnetic field

Examples of electromagnetic disturbance according to its inception:

• Industrial sources of disturbance
• High-current generators while producing the electric energy
• Controlled semiconductor converters with high power ratings
• Every electrotechnical equipment is simultaneously both, a source of electromagnetic interference, as well as its receiver working in a certain electromagnetic environment. For each such device defines a general standard CSN-IEC 01/01/1000 some fundamental terms, whose primary relationship is illustrated in the picture below

We are highly engaged in offering the MOV Based Surge Filters (32A - 63A).

Surge Filter EMI (Electromagnetic Interference) RFI (Radio Frequency Interference) Filters, basically are passive electronic devices that are used to suppress conducted interference that is found on a signal or power line. RFI/EMI Filter will suppress the interference created by other equipment and the interference of the module or system itself, with the desired result being improvement to the immunity from EMI signals in the surrounding setting. RFI/EMI Filters are available in different configurations (Single phase - chassis mountable, PCB mountable, Panel mountable, Three phase - with screw Terminals ,with bus-bar terminals etc). RFI/EMI Filter works by presenting a significantly higher resistance to higher frequency content. In other words, the low pass design of the RFI/EMI Filter (the combination of shunting capacitors and series inductors) results in the restriction/impeding of the flow of high frequency signals, effectively shorting it to ground. The final result of the RFI/EMI Filter is that it reduces and attenuates the unwanted signal strength, thereby having a minimal effect on other components or devices. Elcom has state of art manufacturing facility. Elcom has a dedicated team in the R&D to provide customized filters as per the applications & customer's requirements.

The protection of equipment from threatening electrical disturbances that occur on the power grid and inside customer facilities and the protection of equipment from conducted disturbances (i.e., emissions) are critical to the life and operation of any electronic equipment. These are two issues for manufacturers that must not be taken lightly. Manufacturers are under continued economic pressure to design and manufacture equipment that must perform as their customer expect. Moreover, manufacturers have profit margins that must be met if they are to satisfy their investors and continue to develop new products for our digital society. Equipment failures and malfunctions caused by EMI problems and voltage surges can be dealt with in an economically effective way without compromising equipment protection or performance.

 

Two of the technologies that have grown to be commonly used in product design in the last few decades are passive EMI filters using primarily capacitors and inductors and metal oxide varistors (MOVs), respectively.

EMI filters have been used much longer than MOVs. Many new topologies for EMI filters have been designed and implemented. Essentially all of them make use of additional filter components (i.e. capacitors and inductors) to form multi-stage filters. Thousands of new products routinely fail conducted EMI tests when trying to achieve US or international compliance as defined by rules and regulations attempting to avoid EMI problems. Each and every product designer can a “horror story” when trying to achieve EMC compliance. Forensic analyses of many failed products on the market today revealed that product failures were caused by early MOV failure. Many products also suffer from undetectable damage to EMI filters caused by improper or no protection of filter elements from voltage surges.