The overload relay with the bimetal technology (Thermal Overload) only can be used in DC application.
Tesys LRD Range
Tesys LRD thermal overload relays can be used in a DC application. Series up the connections through the contactor and overload.
Tesys LR9 Range
Do not use the Tesys LR9 Electronic overload relay because under phase failure condition there will be nuisance tripping.