Ground fault protection in IT electrical systems (isolated from ground): ISOMETER® and EDS
 
Insulation monitors or ISOMETER® have the main function of detecting ground faults early in isolated ground systems (IT, ungrounded). They detect these faults in AC and/or DC electrical systems, reaching voltages of 15.5kV L-L. An intrinsic advantage of isolated ground systems is that in the event of a first loss of insulation (ground fault) it is not necessary to interrupt the electrical supply, and operations can continue even in fault conditions. But this advantage would only be effective if an ISOMETER® is available in the installation, which measures the insulation online, that is, it monitors the energized electrical systems in real time. Without an ISOMETER® present we will not know what the state of the installation's insulation is, so we would lose all advantage. 
Finally, the ISOMETER® constant of a pre-alarm and an alarm, when the first is activated we have a window of time (which can be days or weeks and in some cases even months) to correct said ground fault. All of this occurs while the system is energized, that is, at no time have we interrupted operations.