Fully shielded design (sensor and measuring line)
Where space is limited, the grounding and shielded measuring line are positioned opposite (special implementation)
Current load capacity of shielding up to 50A
Resistant to vacuum impregnation
Description
In the NWT-A, the carrier housing is insulated with mica paper. Opposite is a copper plate that is insulated again to the outside with mica. The shield of the feed line is connected to the copper plate. The grounding line is fix connected to the copper plate. The shielding is designed such that, in case of malfunction, the NWT can discharge a fault current of up to 50A via its shield (grounding). This gives the motor contactor a little more time for switch-off. For NWT-A with the ignition protection type “intrinsically safe” (Ex i), floating installation must be ensured. In this case, the grounding line serves only as potential equalisation and can be designed significantly lower in the line cross section if the high current load capacity is not needed.