Izilawuli zokulawula izinga lokushisa kanye namavalvu okulawula izinga lokushisa (ngezinye izikhathi okubizwa ngokuthi i-TCV) aklanyelwe ukulawula izinga lokushisa lenqubo ngokulawula ukucindezela koketshezi olushisayo noma ukugeleza kuma-compressor, amabhantshi amathangi, amakhoyili okufudumeza, noma ezinye izici zokushisisa.