Industrial A-Isometer IR-207 Ground Fault Relay

ISOMETER® IR207(M/L) is a Bender A-Isometer insulation monitoring device designed for IT systems in ungrounded electrical installations. It continuously monitors insulation resistance in IT networks, using a DC measuring voltage superimposed on the live circuit, and provides an output relay (K1) that energizes when the predefined insulation threshold is reached. The device also features an alarm LED to indicate low-ohmic DC faults such as earth faults, enabling quick local fault indication. The IR207 family comprises IR207M and IR207L variants, reflecting different form-factor options within the A-Isometer range. Typical applications include industrial control circuits and machinery where ungrounded networks require ongoing insulation monitoring to prevent insulation deterioration from escalating into faults. By offering a dedicated fault signaling relay and a clear visual indication, IR207 helps meet safety monitoring objectives in IT-based electrical systems.