The thermal overload relays are suitable for overload protection of AC motor operated on 8 hour duty or uninterrupted duty.The overload protected AC motor with requency 50Hz,voltage up to 660V,current up to 40A.Several funcation provided by these relays are phase-faiure protection,temperature compensation,ON/OFF indication and manual/sutomatic reset.The relays comply with IEC292-1 standard.