This device belongs to the Vigilohm range designed to monitor ungrounded/IT electrical networks, in accordance to installation and products standards. According to standards, it is recommanded to equip your systems with Insulation Monitoring Devices (IMD). This device is dedicated to monitoring large and disturbed AC, DC and ACDC systems. It mesures the system insulation resistance by injecting a low frequency AC current between the network and ground. Configuration will be set depending on the installation. Settings are available on the front of the device, through the HMI screen. Settings are related to network type, alarm and pre-alarm thresholds, alarm delay from 0 to 7200 secondes, and others are available. It monitors networks up to 830VAC when connected to neutral, 480V when connected to line, and 480VDC, with up to 500microfarad. The black and white screen can displays insulation resistance from 10 ohms to 10 megohms, capacitance and temporary faults. Auto-test starts automatically every 5 hours, and on demand. In case the system insulation resistance drops below the set threshold, meaning a ground fault occurred, an alarm is triggered thru the IMD output relay. Once no fault is monitored, the alarm is cleared, the alarm relay is back to normal. The device can be supplied by a 24VDC to 48VDC source with a tolérence of plus or minus 15%. This product is installed flush mounted, an enclosure door for example. Front face ingress protection is IP5, rear IP20 and overvolage 300V category III. The monitoring device is equipped with a RS485 communication port, Modbus protocol.