Bender IRDH375B-427 | Insulation Monitoring Device

Specifications

• Measured System Voltage (Un):
  • AC/3NAC: 0–793 V
  • DC: 0–650 V
• Supply Voltage (Us): DC 19.2–72 V, 14 VA max
• Insulation Resistance Range: 1 kΩ – 10 MΩ (two independent alarm thresholds)
• Measuring Principle: AMP Plus (adaptive, high leakage capacitance tolerant)
• Relay Outputs: 2 × alarm relays, AC 250 V / 5 A (NO/NC configurable)
• Communication: RS-485 (Modbus RTU), 0/4–20 mA analog output
• Display: 2-line LC display with backlight
• Memory & Clock: Historical log with real-time clock (time-stamped alarms)
• Operating Temperature: -20 °C to +60 °C
• Mounting: Panel mount, 96 × 144 mm (H×W)
• Weight: Approx. 4 kg

Key Features

1. Continuous IT System Monitoring: For isolated (ungrounded) AC, DC and mixed AC/DC systems.
2. Dual Alarm Thresholds: Two independent, adjustable response values for early warning and critical alarm.
3. Adaptive Leakage Capacitance: Automatically compensates for high system leakage capacitance (common in modern VFD/rectifier installations).
4. Self-Diagnostics & Test: Continuous self-monitoring with automatic self-test; detects broken measurement wires.
5. Industrial-Grade Interface: RS-485 for BMS integration; 0/4–20 mA output for remote resistance indication.

Applications

• IT Systems: Ungrounded power distribution in industrial, medical, and marine environments.
• Power Electronics: Systems with rectifiers, inverters, VFDs, and UPS.
• Critical Infrastructure: Data centers, hospitals, oil & gas, and renewable energy plants.
• Marine & Offshore: Ships, platforms (option "W" for enhanced shock/vibration resistance)Bender GmbH & Co. KG