07.97 12 Functional Descriptions
12.32.8 Reduction zone of a protection zone
Calculation of the number of acceleration steps to brake from V
max
to 0 using a
max
:
m= ; Integer component of the division
v
max
a
max
m
remainder
=; Remainder of the division
v
max
a
max
Calculation of the max. braking distance
· a
max
+m
remainder
· a
max
· m
S
brake_max
=m·(m–1)
2
Axis-specific interface
Axis in reduction in reduction zone: DB32, DR k, bit 3
12.32.9 Reduction factor
The reduction factor is an internal override value which is added to the set path velocity of all
channels of the mode group in which the motion axes of the protection zone are located.
It is calculated as a percentage representing the proportion of the distance between two
protection zones.
Formulas
Calculation of the reduction factor of the protection zone S1 with respect to a second
protection zone S2:
Re dfac
S1
= S
S1S2
S
brake_maxS1
+S
brake_maxS2
· 100%
with S
S1S2
=distance between the two protection zones S1 and S2
Minimum reduction factor
If two protection zones collide the result is a reduction of 0%. This would prevent retraction
from this situation. The axis-specific machine data ”Minimum reduction factor” can be used to
set a lower limit for the reduction factor. It is then possible to retract the protection zones at
the resulting velocity.
In the event of a collision the protection zone boundary is crossed with the velocity resulting
from the minimum reduction factor. For this reason, the minimum reduction factor which
depends on the maximum velocity of the axis must be selected to be as small as possible
( 1%).
Axis-specific machine data
Minimum reduction factor: MD 3936*
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50
12–321
SINUMERIK 840C (IA)