2024-01-24 1/4—IN STR UC T I ON M AN UA LISL-C 440INSULATION MONITORING DEVICE FOR ISOLTAED IT (AC) NETWORKS—GENERALIn IT electrical distribution networks with isolated neutral, the high insulation impedance prevents earth faultsfrom generating currents that would dangerously elevate the potential of exposed conductive parts.Therefore, in case of earth leakage in an IT network, it is not necessary to interrupt the supply, but it is stillessential to continually monitor the insulation level in order to detect faults and restore optimal functioningof the system.The ISL-C 440 is an Insulation Monitoring Device for IT networks with a rated voltage of 400 Vac.By putting a continuous component measure signal between the insulated line and earth, it's possible to con-trol the insulation resistance by reading the dispersion current generated to earth.On the front panel of ISL-C 440, there is signaling for the device ON, signaling for tripping TRIP (low insula-tion), a test and a reset push-button, and a series of micro-switches to regulate the threshold of trip.A changeover contact relay is available to use the low insulation signaling in a remote panel.—ACCESSORIES AND OPTIONSStandard version to be fed by 230 Vac, option version 115 VacIn application on network up to 1000 Vac it’s possible to connect an external adapter type ISL-ADT 1000.—INSTALLATIONThe installation must be carried out by qualified and authorized personnel and in the absence of voltage.Make sure that the instrument is O.K. and that it has not suffered any damage during transport.Make sure that the voltage supply is compatible with the operating voltage of the instrument.The device is a 3 modules (17.5mm) DIN version with snap on 35mm DIN rail.It has a sealable transparent front protection cover.The green LED ON will light up after the connections are set and the instrument is powered on.DESCRIPTION 1. Green LED ON signaling the instrument working.2. Red LED TRIP signaling a trip for low insulation.3. TEST button to test the instrument functionality.4. RESET button to cancel the trip signaling (manual reset).5. Micro-switches to select the threshold of trip.