Inzwa yokucindezela kawoyela iyingxenye ebalulekile yenjini, esetshenziselwa ukulinganisa ingcindezi nokulawula, Isetshenziswa kabanzi kumapayipi enjini ahlukahlukene ezimoto nemikhumbi, amaphrojekthi okucubungula amanzi, ukuhlola nokulawula izinqubo zezimboni ze-rial, iphrojekthi ye-hydraulic kanye ne-pneumatic control s, njll.