SINAMICS S120 Functi.. - Gregbotos.com

Extended FunctionsFunction module “basic positioner”The software limit switch monitoring is inactive during the complete reference pointapproach; only the maximum traversing range is checked. The SW limit switchmonitoring is, if required, re-activated after completion.The selected velocity override is effective only while searching for the referencecam (stop 1). This means that the positions “end of cam” and “zero mark” are alwayspassed with the same velocity. If signal run times (propagation times) occurfor the switching operations, then it is guaranteed that the offset that occurs whendetermining the position is the same at every referencing operation.Axes that only have one zero mark over their complete traversing or modulo rangeare designated with parameter p2607 = 0 (no reference cam present). For theseaxes, after referencing has been started, a start is immediately made to synchronizeto the reference zero mark (refer to step 2).Reference point approach, step 1: Travel to the reference camIf there is no reference cam (p2607 = 0), go to step 2.When starting referencing, the drive accelerates, with the maximum acceleration(p2572) to the reference cam approach velocity (p2605). The approach direction isdefined using the signal of the binector input p2604 (reference point approach,start direction).When the reference cam is reached, this is communicated to the drive using thesignal at binector input p2612 (reference cam); the drive then brakes down tostandstill with the maximum deceleration (p2573).If, during the reference point approach, a signal is detected at binector input p2613(reversing cam, minus) or at binector input p2614 (reversing cam, plus), then thesearch direction is reversed. The reversing cams are low active. If both reversingcams are active (p2613 = “0” and p2614 = “0”), then the drive remains stationary(zero speed). As soon as the reference cam is found, then synchronization to thereference zero mark is immediately started (refer to step 2).If the axis moves from the starting position towards the reference cam, a distancedefined in parameter p2606 (max. distance to the reference cam) without the referencecam being reached, the drive comes to a standstill and fault F07458 (referencecam not found) is output.If the axis is already located at the cam, when referencing is started, then traversingto the reference cam is not executed, but synchronization to the reference zeromark is immediately started (refer to step 2).© Siemens AG 2006 All Rights ReservedSINAMICS S120 Function Manual, 03/2006 Edition4-259