Bokosi la reel ili ndi gawo lofunikira pamakina otetezedwa pamakina omanga, kuphatikiza kuyeza kolondola kwapawiri kwautali ndi ngodya. Amapangidwira ma load moment limiters (LML) a ma cranes am'manja, nsanja zogwirira ntchito zam'mlengalenga, ndi zida zina. Potolera zenizeni zenizeni za kutalika kwa boom ndi ngodya ya luffing, imagwira ntchito ndi wowongolera wamkulu kuti aziwunika kuchuluka kwa katundu wotetezeka, kuletsa kwambiri mikhalidwe yowopsa monga kulemetsa komanso kuchulukirachulukira.

Sensa iyi ndi zida zopangira chingwe ndiye gawo lofunikira kwambiri pamakina owongolera chitetezo pamakina onyamulira, opangidwira ma cranes oyenda, ma crawler, ndi zida zina zauinjiniya. Amapereka nthawi yeniyeni, kuzindikira bwino kutalika kwa kutalika kwa boom ndi ngodya yokwera, kutembenuza deta kukhala zizindikiro zamagetsi zamtundu wa load moment limiter (LML). Izi zimalepheretsa kuchulukitsitsa, rollover, ndi zochitika zina zachitetezo komwe kumachokera, ndikupangitsa kukhala wopanga zida zoyambirira (OEM) kusankha kotsogola kwamtundu wa crane padziko lonse lapansi.

Sensor reel sensor iyi ndi gawo lalikulu lachitetezo pamakina omanga, opangidwira ma cranes am'manja ndi ma cranes amtundu uliwonse. Imaphatikizira masensa olondola kwambiri komanso njira yodziwikiratu yochotsa chingwe kuti izindikire kutalika kwa boom ndi ngodya yokwera, kutumiza deta yeniyeni ku Load Moment Indicator (LMI). Izi zimachotsa ziwopsezo zochulukirachulukira pamagwero, ndikupangitsa kukhala chida chofunikira kwambiri chowonetsetsa kuti chitetezo chikwezedwe.