The Tesys T Ground fault protection monitors only the Vector sum of the 3 phase current and not the earth/ground line separately for any residual current, thus we refer it as the Ground Fault.

TeSys T is not designed to protect people from harm caused by ground current but to protect motor and related equipment.

On TeSys T, the ground fault protection is used to estimate the lifetime of your motor. Old motor will have an increased earth leakage.

To conclude on whether TeSys T can do ground fault protection, you need to refer to your national and local safety regulations and codes to determine if TeSys T tripping characteristics and settings will be suitable for your needs.

There is no such test procedure available for it. You can simply inject the current through the LTMR associated with ZCT and check its behaviour if the vector sum of the three phases is not zero.

For this you need to configure LTMR for ground fault settings and for more information on TeSys T ground fault you may please refer the extract of Tesys T user guide.

Released for: Schneider Electric United Arab Emirates