2CSM341000R1501 ABB ISOLTESTER-DIG-PLUS Insulation Monitor

Why Choose the ABB ISOLTESTER-DIG-PLUS Insulation Monitor?

The ABB ISOLTESTER-DIG-PLUS is an advanced insulation monitoring device for medical IT-M networks, designed to continuously supervise electrical safety while supporting continuity of supply in critical healthcare environments. As part of ABB’s Earth Monitoring Devices and H+ Line range, it detects and signals the first earth fault without requiring immediate interruption of the monitored circuit.

Designed for insulated medical networks, the ISOLTESTER-DIG-PLUS monitors insulation resistance, insulation impedance, network capacitance, transformer temperature and load current. Its codified measuring signal provides enhanced immunity to electrical disturbances commonly generated by medical equipment, helping distinguish genuine insulation faults from interference and reducing unwanted alarm signalling.

The ISOLTESTER-DIG-PLUS also provides RS485 communication with Modbus RTU, minimum and maximum value recording and a programmable output relay. These capabilities allow the monitor to integrate with supervisory systems while providing detailed information about the condition of the medical IT-M network and its associated isolation transformer.

Key Advantages

• Continuous insulation monitoring for medical IT-M networks where continuity of supply is essential.
• Codified measuring signal improves immunity to electrical interference and helps reduce unwanted alarms.
• Monitors insulation resistance, impedance and network capacitance.
• Provides two transformer temperature monitoring inputs and external current-transformer input for load supervision.
• RS485 Modbus RTU communication enables integration with PLC, PC and supervisory systems.
• Stores minimum and maximum measured values to assist fault analysis and maintenance.

Key Features

• ABB H+ Line medical insulation monitoring device.
• Designed for medical IT-M insulated networks.
• 115–230 V AC auxiliary supply, 50–60 Hz.
• Monitors networks from 24–250 V AC/DC.
• Suitable for monitored AC networks from 50–400 Hz.
• 0–999 kΩ insulation resistance measurement.
• 0–999 kΩ insulation impedance measurement.
• 0–9.9 µF network capacitance measurement.
• 50–500 kΩ adjustable low-insulation threshold.
• Codified control signal for improved noise immunity.
• Two temperature inputs for PT100 or PTC probes.
• External current-transformer input for line overload monitoring.
• RS485 serial interface with Modbus RTU protocol.
• Programmable output relay.
• Compatible with up to four ABB QSD remote signalling panels.
• Front TEST, RESET and programming controls with three-digit display and status LEDs.

Advanced Insulation Monitoring for Medical IT-M Networks

Medical IT-M systems are designed to maintain continuity of supply when a first insulation fault occurs, making continuous insulation supervision essential. The ABB ISOLTESTER-DIG-PLUS monitors insulation resistance and impedance while also supervising network capacitance, isolation-transformer temperature and load current. When a monitored parameter exceeds its configured threshold, the device generates an alarm so medical or technical personnel can investigate the condition without unnecessary interruption of the electrical supply.

A key feature of the ISOLTESTER-DIG-PLUS is its codified measuring signal, designed to improve measurement reliability in electrically noisy medical environments. Equipment such as imaging systems, displays, sterilisation equipment and other electronic loads can introduce disturbances into the network; the codified signal helps the monitor distinguish these disturbances from genuine insulation faults. RS485 Modbus RTU communication, minimum and maximum value storage and programmable relay functionality further support integration into modern hospital monitoring and building-management systems.

Typical Applications

• Medical IT-M electrical distribution networks.
• Group 2 medical locations.
• Operating theatres and surgical suites.
• Intensive care and critical-care environments.
• Medical isolation transformer monitoring.
• Hospital electrical distribution and supervision systems.
• Healthcare installations requiring remote monitoring via RS485 Modbus RTU.