Method for monitoring the state of the earthing contacts of a contactor controllable by means of an exciter coil

The present invention relates to a method for monitoring the state of the earthing contacts of a contactor controlled by an exciter coil, said contactor being operated as part of an isolation unit for galvanically isolating a voltage source from an electric consumer device connected to the voltage source, wherein a first power loss (22), which is transferred via the earthing contacts, and a second power loss (23), which is transferred via the exciter coil, are detected, and the first power loss (22) and the second power loss (23) are fed as input variables to a thermal model (21) of the contactor, the thermal model (21) determines an earthing contact temperature (24) according to at least one of the input variables and provides said contactor temperature as an output variable, and the provided earthing contact temperature (24) is evaluated. 本发明涉及种用于对能够借助于励磁线圈来控制的接触器的、接触器触点的状态进行监控的方法，所述接触器作为用于在电方面将电压源与被连接在所述电压源上的电的耗件设备分离的分离单元的部分来运行，其中求得通过所述接触器触点来转换的第损耗功率（22）和通过所述励磁线圈来转换的第二损耗功率（23），将所述第损耗功率（22）和所述第二损耗功率（23）作为输入