The stepped base and use of a ring clamp allow virtually seamless mounting of the capacitors on a heat sink. The low-inductance GW series is therefore suitable for applications with high ripple currents in a broad temperature range from -40 to 105 °C.
These aluminium electrolytic capacitors with a threaded connection are insensitive to high ripple currents, such as those that occur in auxiliary power converters of urban rail cars or in welding inverters. As a side effect, however, the high currents also cause increased temperatures in the capacitors. Special winding constructions therefore ensure optimal heat dissipation at the capacitor base. In addition, FTCAP has optimised the GW series with optional base cooling by means of a Sil-Pad that dissipates the heat.
A special feature of the GW series is the patented stepped base: This design ensures that the base of the capacitor is flat despite the adjacent heat shrink tube. Air inclusions are therefore reduced, which would hinder dissipation of heat from the capacitor to the heat sink. Thermal resistance is substantially lower, for processing of high loads despite the compact design. In addition, the cup features an outer bead, which allows seamless mounting of the capacitor to a heat sink by means of a ring clamp manufactured in-house by FTCAP. A positive side effect is that the pad and the use of a ring clamp for mounting electrically insulate the capacitor from the heat sink. This provides a large leakage distance that prevents the flow of residual earth-fault currents.
FTCAP GmbH - www.ftcap.de