- Nominal voltage IT system: DC, AC, 3AC 21 - 500 V
- Width: 105 mm
- Bus interface: Modbus RTU, RS-485
- Automatic and fast localisation of faulty circuits
- Increased reliability and availability of the system
- Optimal planning of maintenance and repair work
- No manual and time-consuming fault detection
- Simple operation
- Monitoring of complex systems
Insulation fault location in unearthed AC/DC systems (IT systems)
In extensive industrial plants, locating insulation faults can be expensive and time-consuming. The insulation fault location system enables automatic and fast location of faulty circuits in complex isolated AC/DC systems (IT systems), thus increasing reliability and plant availability. The investment costs for insulation fault location are immediately amortized due to the lower maintenance costs and the avoidance of operational interruptions.
The use of unearthed power supply (IT) systems can improve equipment reliability because in the event of a single-pole direct ground fault, power is maintained and the equipment can continue to operate. Protective elements such as circuit breakers or fuses do not respond until a second fault occurs. Immediate fault rectification is therefore required. DIN VDE 0100-410 also recommends for IT systems that an initial insulation fault be rectified as quickly as possible.
The insulation fault location system of the VARIMETER EDS family (Earth-Fault Detection System), consisting of the RR 5886 test current generator and the RR 5887 insulation fault locators, automatically locates the source of the fault. During operation, you receive all the necessary information about faulty circuits and load feeders, which is particularly important in widely branched and complex systems. The maintenance and servicing of your plant can thus be optimally planned. The iso fault location system is suitable for use in a wide range of industries.
Functional principle of insulation fault location (insulation fault location system)
The search process of the RR 5886 test current generator is usually started by an insulation monitor when the value falls below the response value. The test current generator feeds a test signal into the IT system. In conjunction with the RR 5887 insulation fault locators and the residual current transformers (measuring current transformers) connected to them, this limited test current is evaluated and the insulation fault is localized in the IT system. By connecting several insulation fault locators via an RS-485 bus connection, the number of measuring channels can be increased in steps of either 4 or 8 channels, thus refining the search for insulation faults in widely branched unearthed power supply systems. Insulation fault current values can optionally be read out from the connected devices via the Modbus RTU interface.
Two different signaling levels, pre-warning and alarm, enable early detection of faulty loads. Thanks to automatic balancing of the residual current transformers and clear design of the setting and display elements, the insulation fault location system of the VARIMETER EDS family is easy and intuitive to operate. The early detection and localization of insulation faults allows them to be rectified quickly and in a targeted manner. As a user, you benefit from the operational reliability and high availability of your IT system.
Insulation fault location principle circuit
The circuit example shows the principle structure of a selective insulation monitoring system with the test current generator and the insulation fault locator. As soon as an insulation monitor installed in the IT system reaches its response value, it triggers the test current generator and this automatically starts insulation fault location. The generated test signals are recorded and evaluated by means of the connected residual current transformers. Light emitting diodes assigned to the transformers allow easy localization of a faulty load feeder. To ensure that the insulation monitor does not influence the insulation fault location, the test current generator generates a switch-off signal at its terminals for the measuring circuit of the insulation monitor.
Do you need the right insulation monitoring device for insulation fault location?
To locate insulation faults in unearthed power supply systems, an insulation monitor is also used. When the insulation monitor reaches its response value, it triggers the test current generator, which then automatically starts insulation fault location. Insulation monitoring devices monitor the insulation resistance in unearthed IT systems.