Siemens SINAMICS S120 Function Manual page 297

speed. If signal propagation delays arise during switching processes, this ensures that the
offset caused during establishment of position is the same in each referencing process.
Axes that only have one zero mark over their complete traversing or modulo range are
designated with parameter p2607 = 0 (no reference cam present). After starting the
referencing process, synchronization to the reference zero marks is started straight away
(see step 2) for these axes.
Search for reference, step 1: travel to reference cam
If there is no reference cam present (p2607 = 0), go to step 2.
When the referencing process is started, the drive accelerates at maximum acceleration
(p2572) to the reference cam approach velocity (p2605). The direction of the approach is
determined by the signal of binector input p2604 (search for reference start direction).
When the reference cam is reached, this is communicated to the drive using the signal at
binector input p2612 (reference cam); the drive then brakes down to standstill with the
maximum deceleration (p2573).
If a signal at binector input p2613 (reversing cam, MINUS) or at binector input p2614
(reversing cam, PLUS) is detected during reference point approach, the search direction is
reversed.
If the minus reversing cam is approached in the positive direction of travel or the plus
reversing cam in the negative direction of travel, fault message F07499 "EPOS: Reversing
cam approached from the wrong direction" is generated. In this case, the reversing cam
connections must be checked (BI: p2613, BI: p2614) or the direction of approach to the
reversing cam.
The reversing cams are low active. If both reversing cams are active (p2613 = "0" and p2614
= "0"), the drive remains stationary. As soon as the reference cam is found, then
synchronization to the reference zero mark is immediately started (refer to step 2).
If the axis leaves its start position and travels the distance defined in parameter p2606 (max.
distance to reference cam) heading towards the reference cam without actually reaching the
reference cam, the drive remains stationary and fault F07458 (reference cam not found) is
issued.
If the axis is already located at the cam, when referencing is started, then traversing to the
reference cam is not executed, but synchronization to the reference zero mark is
immediately started (refer to step 2).
Drive functions
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
Function modules
7.9 Basic positioner
297