Insulation fault location in coupled systems
ISOMETER® iso685-D-P insulation monitoring device with EDS44x insulation fault locator and IOM441 input/output module.
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EDSsync function
The example in Figure 1 shows how the right iso685-D-P is deactivated by an auxiliary contact in the coupling switch as soon as the two systems are coupled.
If one of the two devices detects an insulation fault, it automatically switches to insulation fault location operating mode. When the EDSsync function is activated, a search for insulation faults is performed simultaneously on both sides of the coupling switch, even if the right iso685-D-P is deactivated due to the closed coupling switch.
IOM441 input/output module
Up to 50 EDS can be connected to an iso685-D-P. By combining EDS44x with the IOM441 input/output module, a potential-free contact can be made available for each EDS44x measurement channel. This enables messages to be generated or outputs with unimportant loads to be disconnected so that the IT system can maintain high availability for important loads.
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Plain text messages facilitate the search
New measuring methods also make it possible to locate high-impedance faults with high system leakage capacitances and low locating currents. The faulty channels are indicated on the display of the iso685-D-P and can be replaced by plain text messages. This makes fault localisation even easier.
Communication
The iso685-D-P can communicate via Modbus TCP, Modbus RTU and isoData. This ensures that the device can be easily integrated into existing communication solutions.
