Ground-fault location: The concept
How does a ground-fault location system work?
A ground-fault location system comprises a ground-fault test device and a ground-fault evaluator connected to one or more measuring current transformers. The ISOMETER® of the
iso685 series features a built-in ground-fault test device.
Functional sequence
- Start ground-fault location by activating the ground-fault test device ISOMETER®.
- The ground-fault test device briefly connects the live conductors to ground.
- Electronic current limiting, this connection and the ground fault create a closed circuit, in which a test current is determined by the system voltage flows. The test current is limited to a maximum value.
- The test current pulse flows from the ground-fault test device via the live conductors, the ground fault Rf and the ground wire (PE conductor) and back to the ground-fault test device.
- The test current signal is detected by all measuring current transformers on the circuit and evaluated by EDS ground-fault evaluators.
- The fault location can be identified using the assignment between measuring current transformers and circuit.
