, ▁▁▁▁▁ ▁over ▁distances ▁up ▁to ▁ 4 , 0 0 0 ▁feet ▁and ▁is ▁suitable ▁for ▁extreme ▁safety ▁applications . ▁An ▁Opt om ux ▁system ▁is ▁typically ▁made ▁up ▁▁▁▁▁ ▁of ▁three ▁main ▁elements : ▁▁ ▁There ▁must ▁be ▁a ▁host ▁device ▁to ▁poll ▁the ▁Opt om ux ▁brain ▁bo ards . ▁ ▁There ▁are ▁the ▁brain ▁bo ards ▁themselves , ▁anywhere ▁from ▁one ▁to ▁ 2 5 5 ▁of ▁them . ▁ ▁Each ▁Opt om ux ▁brain ▁board ▁attach es ▁to ▁an ▁I / O ▁mount ing ▁ra ck , ▁carrying ▁the ▁individual ▁I / O ▁modules . ▁ ▁Lim itation ▁The ▁primary ▁performance ▁limitation ▁of ▁▁▁▁▁ ▁the ▁Opt om ux ▁system ▁is ▁the ▁slow ▁serial ▁data ▁link . ▁The ▁maximum ▁data ▁rate ▁supported ▁by ▁the ▁Opt om ux ▁▁▁▁▁ ▁brain ▁bo ards ▁is ▁ 3 8 . 4 ▁k bit / s ▁( also ▁dependent ▁on ▁the ▁length ▁of ▁the ▁communication ▁▁▁▁▁ ▁lines ). ▁In ▁theory , ▁at ▁maximum ▁speed , ▁the ▁Opt om ux ▁▁▁▁▁ ▁system ▁should ▁be ▁capable ▁of ▁pol ling ▁roughly ▁▁▁▁▁▁ 3 , 4 0 0 ▁digital ▁positions ▁per ▁second , ▁or ▁roughly ▁▁▁▁▁▁ 6 0 0 ▁analog ▁positions ▁per ▁second . ▁This ▁is ▁▁▁▁▁ ▁assuming ▁that ▁all ▁the ▁positions ▁are ▁on ▁the ▁▁▁▁▁ ▁same ▁brain ▁board , ▁which ▁is ▁not ▁possible ▁with ▁▁▁▁▁ ▁Opt om ux . ▁A ▁more ▁real istic ▁speed ▁figure ▁would ▁▁▁▁▁ ▁be ▁about ▁half ▁of ▁the ▁previous ▁numbers . ▁For ▁▁▁▁▁ ▁faster ▁serial ▁data ▁communication , ▁Opt o ▁ 2 2