Description
The Bender IRDH575B1-427 is an insulation monitoring device designed for unearthed IT power systems. It continuously monitors insulation resistance in AC, DC, and AC/DC systems and provides an alarm when the insulation resistance falls below a configured response value.
The device is part of the Bender ISOMETER® IRDH575 series and is suitable for industrial power systems where early detection of insulation deterioration is important for electrical safety and system availability. The IRDH575B1-427 version is designed for nominal systems from 20 to 575 V and uses a 19.2 to 72 VDC supply.
🔧 Main Features
✔ Continuous insulation resistance monitoring
✔ Suitable for unearthed IT systems
✔ Compatible with AC, DC, and mixed AC/DC systems
✔ Suitable for 3-phase and single-phase industrial applications
✔ Adjustable insulation response values
✔ Integrated alarm and monitoring functions
✔ LCD display for operating information and measured values
✔ RS-485 communication interface for system integration
✔ Supports insulation fault location systems with compatible external devices
✔ Designed for industrial power distribution and control applications
Bender insulation monitoring devices continuously supervise the insulation resistance between an unearthed system and protective earth, allowing insulation deterioration to be detected while the electrical system remains in operation.
📋 Product Datasheet
🏷️ Brand: Bender
🔢 Model: IRDH575B1-427
📚 Series: ISOMETER® IRDH575 Series
📦 Product Name: Insulation Monitoring Device
⚙️ Product Type: Insulation Resistance Monitoring Device
🔌 Nominal System Voltage: AC 20–575 V / DC 20–575 V
⚡ Supply Voltage: DC 19.2–72 V
🛡️ Application: Unearthed IT Power Systems
📊 Insulation Monitoring Range: 1 kΩ to 10 MΩ
🔧 Test Current: Configurable according to the applicable IRDH575 measuring configuration
🔄 Supported Systems: 3(N)AC, AC, DC, and AC/DC systems
📡 Communication Interface: RS-485
🧠 Communication Protocol: BMS
🔗 Address Range: 1–30
🚨 Alarm Outputs: 3 changeover contacts
🖥️ Display: 4 × 20 character LCD display
📐 Panel Cut-Out: Approximately 138 × 90 mm
📏 Front Dimensions: Approximately 144 × 96 mm
🔩 Installation: Panel mounting
🏭 Industrial Application: Power distribution and insulation fault monitoring
⚖️ Weight: Verify according to the physical product version
🌍 Country of Origin: Verify from the product nameplate
✨ Product Condition: New Surplus
The IRDH575B1-427 ordering information identifies this version as suitable for AC/DC nominal system voltages up to 575 V with a 19.2–72 VDC supply.
💡 Typical Applications
The IRDH575B1-427 can be used in industrial systems where continuous insulation monitoring is required without intentionally grounding the monitored electrical system.
Common applications include:
⚡ Industrial IT power distribution systems
🏭 Manufacturing facilities
🛢️ Oil and gas installations
🚢 Marine and offshore electrical systems
🚰 Water and wastewater facilities
⚙️ Converter and rectifier applications
🔋 DC power systems
🏗️ Infrastructure power systems
📡 Remote industrial installations
🔄 Mixed AC/DC industrial networks
The IRDH575 series is suitable for universal use in unearthed AC, DC, and mixed AC/DC systems and can be integrated with compatible insulation fault evaluation equipment for fault-location applications.
❓ FAQ
🔹 Q1: What is the Bender IRDH575B1-427 used for?
A: It is used to continuously monitor insulation resistance in unearthed IT electrical systems. If insulation resistance falls below the configured response value, the device generates an alarm.
🔹 Q2: What voltage systems can this model monitor?
A: The IRDH575B1-427 is designed for nominal AC and DC system voltages from 20 to 575 V.
🔹 Q3: What power supply does the IRDH575B1-427 require?
A: This version uses a DC auxiliary supply voltage of 19.2 to 72 V.
🔹 Q4: What is an IT system?
A: An IT system is an electrical distribution system in which the active conductors are isolated from earth or connected to earth through a high impedance. Insulation monitoring is used to detect developing insulation faults between the system and protective earth.
🔹 Q5: Can the device monitor DC systems?
A: Yes. The IRDH575 series is designed for AC, DC, and mixed AC/DC systems, and the B1-427 version supports DC nominal system voltages up to 575 V.
🔹 Q6: Does the device provide communication capability?
A: Yes. The IRDH575 series includes an RS-485 interface using the Bender BMS communication system, allowing integration with compatible monitoring equipment.
🔹 Q7: Can the IRDH575B1-427 be used for insulation fault location?
A: The device can be integrated with compatible insulation fault evaluation equipment and measuring current transformers as part of an insulation fault location system.
🔹 Q8: What should be checked before replacing an existing unit?
A: Verify the complete model number, monitored system voltage, auxiliary supply voltage, panel dimensions, communication wiring, alarm relay configuration, and connected insulation monitoring equipment.
🔹 Q9: Is this model suitable for industrial spare parts inventory?
A: Yes. Insulation monitoring devices can be important spare parts in critical unearthed power systems because their failure may reduce insulation supervision and fault detection capability.
🔹 Q10: Why must the exact suffix B1-427 be verified?
A: Different IRDH575 versions have different nominal system voltage ranges and auxiliary power supply requirements. The complete model number should always match the installed system requirements.
🔍 Recommended Bender Models
• Bender IRDH575B1-427
• Bender IRDH575B1-435
• Bender IRDH575B1-4227
• Bender IRDH575B1-4235
• Bender IRDH575B2-427
• Bender IRDH575B2-435
• Bender iso685-D
• Bender iso685-S
• Bender iso175
• Bender IR1575
📦 Procurement Tip
Before purchasing a replacement Bender IRDH575B1-427, verify the complete model number directly from the installed device label. Pay particular attention to the monitored system voltage range of AC/DC 20–575 V and the auxiliary supply requirement of DC 19.2–72 V. Also check the RS-485 communication configuration, alarm relay wiring, panel mounting dimensions, and compatibility with any connected insulation fault location system.
