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VS capacitors either comply with or have been approved according to current European standards. The requirements that metallised polypropylene film fluorescent lamps have to meet are fundamentally specified in EN 61048 and EN 61049. In accordance with these standards and their respective construction type, capacitors are broken down into unsecured type A capacitors and secured type B capacitors (hermetically sealed with a contact breaker). Type B capacitors are still often referred to as flame- and explosion-proof capacitors with a break-action mechanism.
All type A capacitors are optionally available with a thermal fuse that cuts the power in the event of overheating, especially at the end of the capacitor´s service life. This model is protected by European patent no. 0637040. Type A capacitors with a thermal fuse are therefore safer than type A capacitors without any form of protection. However, a certain basic risk still remains with type A capacitors. High-grade, secured type B capacitors are therefore always used for higher cut-off voltages and capacitances.
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In addition to being well insulated and very small, metallised polypropylene film dielectric capacitors are self-sealing and can withstand brief periods of excess voltage. Depending on the respective nominal voltage and construction type, capacitors are produced in dry versions and ones with an ecologically harmless liquid insulation filling.
Both IDC terminals and push-in twin terminals with integrated discharge resistors can be used for standard electrical connections. Double flat connectors can be used for larger capacitor types. The discharge resistor ensures the capacitor is discharged down to 50 V within 60 seconds. Resin-filled capacitors should always be mounted in an upright position; dry capacitors can be mounted any way up. A longitudinal clearance of approx. 10 mm must be allowed when mounting type B capacitors because the casing will expand by up to 8 mm in the event of the break-action mechanism being activated at the end of the capacitor´s service life.
The temperature ranges specified for the capacitors refer to the actual surface temperature of the casing. Capacitors should therefore never be mounted near sources of heat or radiated heat. Overheating the capacitor or subjecting it to long-term excess voltage (> 1.1UN ) will drastically shorten its service life.
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