Re: IT earthing system: FOR or AGAINST?

Home Electrical Engineering Forum General Discussion IT earthing system: FOR or AGAINST? Re: IT earthing system: FOR or AGAINST?

Spir Georges GHALI

Dears ;


As we have many types of ” Earthing System “, and each one of them has advantages & disadvantages, so, Mr. Laurent mentioned to the advantages of ” IT system ” that are :

– Too limited value of the 1st fault's current that means long life of equipments.

– The continuity of service : very very important in some applications like Hospitals.

– By using the ” IMD “, we will have an idea about the insulation's level of the networks that means : optimizing of maintenance.

– Ext…

These advantages can't be realized by another system.


Certainly this system is expensive and in some cases ( depending on realisation ) we spend some time to locate the place of the fault, but we need it in some applications. As we have, for 3 phases IT, 2 main types ” IT without distribution of Neutral  &  IT with distribution of Neutral ” ( depending on the loads' type ), so by choosing the correct one and using the correct ” IMD equipments ” ( depending on the cost ), the IT will be reliable and very usefull.