Igwe ọkụ na-ekpo ọkụ na-ekpo ọkụ nke ụgbọ ala eletrik dị ọcha enweghị ike izute mkpa nke kpo oku oyi, ya mere kpo oku oyi bụ nsogbu nke ụgbọ ala eletrik dị ọcha kwesịrị idozi.Ndị na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ (positive okpomọkụ coefficient, PTC) bụ nke PTC seramiiki kpo oku na tubes aluminom, nke nwere uru nke obere nguzogide okpomọkụ na oke ọkụ na-ebufe ọkụ, ma na-agbanweghị ya na ndabere nke ụgbọ ala mmanụ ụgbọala.