Siemens SINUMERIK 808D Function Manual page 65

Evaluation
The traversing path/velocity produced by rotation of the handwheel is dependent on the following factors:
● Number of handwheel pulses received at the interface
● Active increment (machine function INC1, INC10, INC100, ... )
An increment is evaluated with 0.001 mm if the basic system setting is metric.
● Pulse weighting of the handwheel using general MD11320 HANDWH_IMP_PER_LATCH (handwheel pulses per locking
position)
Motion command +/-
While the axis is moving, the "Travel command+" or "Travel command-" interface signal is transmitted to the PLC depending
on the direction of motion.
● For geometry axes: DB3300.DBX1000.7/.6, DB3300.DBX1004.7/.6, DB3300.DBX1008.7/.6
● For machine axes / spindle: DB390x.DBX004.7/.6.
If the axis is already being moved using the traversing keys, the handwheel cannot be used. Alarm 20051 "Jogging with the
handwheel not possible" is output.
Velocity
The velocity results from the pulses generated by the handwheel and the pulse evaluation: Traverse path per time unit. This
velocity is limited by the value in the axis-specific MD32000 MAX_AX_VELO.
Abortion/interruption of traversing movement
The traversing movement is aborted as the result of a RESET or the axis-specific IS "Deletion of distance-to-go"
(DB380x.DBX0002.2). The setpoint/actual-value difference is deleted.
NC STOP only interrupts the traversing movement. NC START releases the handwheel motion again.
Movement in the opposite direction
Depending on MD11310 HANDWH_REVERSE, the behavior when the traversing direction is reversed is as follows:
● MD value = 0:
If the handwheel is moved in the opposite direction, the resulting distance is computed and the calculated end point is
approached as fast as possible: If this end point is located before the point where the moving axis can decelerate in the
current direction of travel, the unit is decelerated and the end point is approached by moving in the opposite direction. If
this is not the case, the newly calculated end point is approached immediately.
● MD value > 0:
If the handwheel is moved in the opposite direction by at least the number of pulses indicated in the machine data, the
axis is decelerated as fast as possible and all pulses received until the end of interpolation are ignored. That means,
another movement takes place only after standstill (setpoint side) of the axis (new function).
Response at software limit switches
When axes are traversed in "JOG" mode, they can traverse only up to the first active limitation before the corresponding
alarm is output.
Depending on the machine data MD11310 HANDWH_REVERSE, the behavior is as follows (as long as the axis on the
setpoint side has not yet reached the end point):
● MD value = 0:
The distance resulting from the handwheel pulses forms a fictitious end point which is used for the subsequent
calculations: If this fictitious end point is positioned, for example, 10 mm behind the limitation, these 10 mm must be
traversed in the opposite direction before the axis traverses again. If a movement in the opposite direction is to be
performed immediately after a limit, the fictitious distance-to-go can be deleted via IS "Delete distance-to-go"
(DB380x.DBX0002.2) or by deselecting of the handwheel assignment.
● MD value > 0:
All handwheel pulses leading to an end point behind the limitation are ignored. Any movement of the handwheel in the
opposite direction leads to an immediate movement in the opposite direction, i.e. away from the limitation.
Function Manual
01/2017
65