The iso685D-P variant of the Bender insulation monitoring device ISOMETER® iso685-D can be used for systems with insulation fault location. An integrated locating current generator creates a limited locating current to earth when an insulation fault occurs. This locating current can be adjusted. With insulation fault locators of the ISOSCAN® series, this locating current can be assigned to a defective load using a measuring current transformer. The iso685-D-P can communicate with the insulation fault locators EDS440 and EDS441 via an RS-485 sensor bus or via a backbone bus. All required settings for the EDS440 and EDS441 can be made via the iso685-D-P. It is possible to program each channel separately or all channels together.
New measuring methods allow locating 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. For example, in the event of an insulation fault on a motor the message "Insulation fault compressor 1" could be displayed. This allows the location of a fault without having to study the wiring diagram and therefore facilitates the insulation fault location. Of course, all the features of the iso685-D-B variant are included in the iso685-D-P.
In DC systems, the iso685-D-P can be triggered and issue a prior warning if there is a DC shift voltage measured against earth. The corresponding response values for these prior warnings and the disconnection can be adjusted in 5-V steps.