The ISOMETER® iso685-… is an insulation monitoring device for IT systems in accordance with IEC 61557-8. It is universally applicable in AC, 3(N)AC, AC/DC and DC systems.
AC systems may include extensive DC-supplied loads (such as rectifiers, inverters, variablespeed drives).

• AC, DC or AC/DC main circuits
• AC/DC main circuits with directly connected DC components, such as rectifiers, converters, regulated drives
• UPS systems, battery systems
• Heaters with phase control
• Systems including switch-mode power supplies
• IT systems with high leakage capacitances

• Insulation monitoring for unearthed systems AC, 3(N)AC 0…690 V, DC 0…1000 V
• Nominal system voltage expandable via coupling devices
• Two separately adjustable response values 1 kΩ…10 MΩ
• Combination of AMPPLUS and other profile-specific measurement methods
• Continuous measurement of capacitance, voltage and system frequency
• Predefined measurement profiles to meet different requirements
• Automatic adaptation to the system leakage capacitance
• INFO button to display device and network settings
• Self-monitoring with automatic alarm message
• History memory with real-time clock (buffer for three days) for storing 1023 alarm messages with date and time
• Current and voltage output 0(4)…20 mA, 0…400 μA, 0…10 V, 2…10 V (galvanically separated) which is analogous to the measured insulation value of the system
• Permanent coupling monitoring of the measuring lines
• Freely configurable digital and analogue inputs and outputs
• Two separate alarm relays with potentialfree contact
• N/O or N/C operation selectable
• High-resolution graphic LC display
• IsoGraph function for time-related representation of the insulation resistance
• Remote setting of certain parameters via Internet (web server/option; COMTRAXX® Gateway)
• Worldwide remote diagnosis via Internet
• Modbus TCP, web server and BCOM
• Multilingual