Terata ea constantan ea koporo ea nickel alloy, e nang leho hanyetsa motlakase ho tlase, e hanela mocheso hantle ebile e hanela mafome, e bonolo ho sebetsoa le ho tjheseletsa ka loto. E sebedisetswa ho etsa dikarolo tsa bohlokwa ho relay ya ho fetisa mocheso, breaker ya potoloho ya mocheso e hanyetsanang le maemo a tlase, le disebediswa tsa motlakase. Hape ke thepa ya bohlokwa bakeng sa thapo ya ho futhumatsa ya motlakase. E tshwana le ya mofuta wa cupronickel.