RAILWAY CERAMIC SECURITY CAPACITORS

The two main failure modes which can affect capacitors over their life time and endanger an

electronic circuits operation are open circuit and short circuit.While short circuits are generally easily detected, open circuits however can be extremely difficult.This failure mode can also be dangerous because in this case the capacitor no longer assures its function.In certain equipment such as security systems for automatic pilot it is necessary to be able to detect any

change in the capacitor which suggests that the capacitor could become open circuit. The standard NFF 62-102, which applies to signalling equipment for rail networks, requires the use of "controllable" capacitors terminal security capacitors are specially designed to control any deterioration in their own performance which could suggest a tendency towards an open circuit during the life cycle of the equipment concerned. Their internal configuration (crossed Electrodes) with 2 terminals for each polarity assures that the capacitor will continue to

function if one of the terminals looses contact. This also permits the equipment to detect the anomaly so preventive maintenance can take place. They can also avoid problems related to short circuits cracks caused when soldering which makes this range of components

the most reliable on the market today. This range (see data sheet attached) is composed of:

- NPO (Type 1) capacitors for applications requiring precise and stable capacitance values

- 2C1 or X7R (Type 2) capacitors where high capacitance values are necessary

These capacitors are designed for surface mount use and can be mounted as follows:

- Directly on the PCB

- Using mini ribbon terminals which absorb thermo mechanical constraints when soldering

and in operation so guaranteeing an even higher level of reliability.

FOR A DATA SHEET OF Eurofarad safety caps click here