Abstract: The present invention relates to a method (400) for determining a grounding impedance (210) of a grounding device (120) of a power engineering installation (110). The method comprises determining (406, 412) at least two impedance values on the grounding device (120), while the grounding device (120) is electrically connected to at least one further grounding device of at least one further power engineering installation (170, 180). Each of the at least two impedance values is determined with a respective test current at a specified frequency. The frequencies of the respective test currents are different. The method further comprises determining (414) at least one parameter of a model (500), which represents the grounding device (120) and the at least one further grounding device, as a function of the at least two impedance values. The at least one parameter comprises an approximate value for the grounding impedance (210) of the grounding device (120).

Abstract: The present invention relates to a method (200) for testing a wiring of an electrical installation (100) comprising multiple circuits. In the method (100), multiple test signals (160-162) are generated. Each of the multiple test signals (160-162) has an asymmetrical signal shape in the time domain and also a combination of harmonics from a predefined group of higher harmonics. The combinations of harmonics of the multiple test signals (160-162) are different. The multiple test signals (160-162) are fed at a first point (141) of the electrical installation (100) into multiple first connections (142-144), which are assigned to the multiple circuits. Multiple measurement signals are detected at multiple second connections (146-148), which are assigned to the multiple circuits, at a second point (145) of the electrical installation (100).

Abstract: The present invention relates to a method for testing wiring of an electrical installation having multiple circuits. In the method, multiple test signals are generated. Each of the multiple test signals has a combination of predefined harmonics having at least one higher harmonic, wherein the amplitude and/or phase of the at least one higher harmonic of the multiple test signals are different. The multiple test signals are injected into multiple first connections, which are assigned to the multiple circuits, at a first point of the electrical installation.

Abstract: An apparatus for moving a tractor cab relative to a tractor body includes a bracket having a first end and a second end, the first end of the bracket being secured to the tractor body and the second end of the bracket being spaced apart from the tractor body. The apparatus also includes a first support arm having a first end and a second end, the first end of the first support arm being secured to the tractor cab and the second end of the first support arm being secured to the second end of the bracket.

Abstract: The tractor includes a frame member mounted in the tractor body and a first mounting member secured to the frame member, the first mounting member including a plurality of first apertures. The tractor also includes a bracket for supporting a cab riser apparatus thereon, the cab riser apparatus being capable of moving the tractor cab relative to the tractor body. The tractor further includes a second mounting member secured to the bracket. The second mounting member including a plurality of second apertures which align with the plurality of first apertures. A method of mounting a bracket onto a frame member of a tractor body is also disclosed.