Requirement profile must be convincing worldwide
The requirement profile is extensive: the capacitor should be firmly seated in the mounting plate. In addition, the seal must allow exact movement tolerances. Since the inverters are in demand worldwide, very different climatic conditions must be expected. For example, no earth moisture or air humidity may reach the capacitors or the electronics area in the inverter; this could cause damage. For this reason, Jäger‘s seal must seal both to the metal sheet and to the individual capacitors.
In addition, the selected material must comply with fire protection guidelines. In this case the US American fire standard UL 94 HB applies. This defines the maximum length of time this seal may burn in the event of a fire. This is based on the relative temperature index of 110 degrees Celsius.
Another point: How can the seal between the sheet metal and the capacitor be optimally inserted? The tests quickly show that the seal cannot be anchored in the sheet metal without an additional clamping ring. But how must this ring be designed so that it sits firmly and securely in the sheet metal opening?