ISOMETER® isoRW425

• Insulation monitoring device for AC and DC IT systems

• Application control circuits in railway vehicles according to EN 50155

• Insulation impedance measurement (Z mode) for 50 Hz or 60 Hz

• Automatic adaptation to the system leakage capacitance up to 300 μF

• Measurement of the nominal system voltage (RMS) with undervoltage and overvoltage detection

The ISOMETER® monitors the insulation resistance (R mode) or the insulation impedance (Z mode) of unearthed AC/DC main circuits (IT systems) with nominal system voltages of 3(N)AC, AC, AC/DC or DC 0…440 V. DC components existing in 3(N)AC, AC/DC systems do not influence the operating characteristics when a minimum load current of DC 10 mA flows. Due to the separate supply voltage, de-energised systems can also be monitored. The maximum permissible system leakage capacitance C_e is 300 μF in R mode and 1μF in Z mode.

Features

• Monitoring of the insulation resistance (R mode) or the insulation impedance (Z mode) of unearthed 3(N)AC, AC and

• DC systems (IT systems) with galvanically connected rectifiers or inverters

• Insulation impedance (Z mode) for 50 Hz or 60 Hz

• Measurement of the nominal system voltage (RMS) with undervoltage and overvoltage detection

• Measurement of DC voltages system to earth (L+/PE and L-/PE)

• Automatic adaptation to the system leakage capacitance up to 300 μF in R mode and 1μF in Z mode

• Automatic device self test with connection monitoring

• Selectable start-up delay, response delay and delay on release

• Two separately adjustable response ranges of 1…990 kΩ (Alarm 1, Alarm 2)

• Alarm signalling via LEDs (AL1, AL2), a display and alarm relays (K1, K2)

• N/C operation or N/O operation selectable

• Measured value indication via multifunctional LCD

• Fault memory can be activated

• RS-485 (galvanically isolated) interface including the following protocols:
  – BMS interface (Bender measuring device interface) for data exchange with other Bender components
  – Modbus RTU
  – isoData (for continuous data output)

• Password protection to prevent unauthorised changes of parameters

Applications

• AC control circuits in industry, mechanical engineering, power stations, elevators, automation systems and railway systems in accordance with EN 50155

• AC control and auxiliary circuits in accordance with DIN EN 60204-1 “Electrical equipment of machines”, IEC 60204-1, EN 60204-1

• AC auxiliary circuits in accordance with DIN VDE 0100-725

• Smaller AC IT systems such as lighting systems, mobile generators