Operating instructions

104 Application manual Positioning 04/08
4.9 Speed Override
The positioning function uses the parameterized speeds of the individual motion
blocks.
Alternatively, the positioning speed can be defined via an external reference value
source. For this purpose, the
Speed Override 1236 function is enabled. The set
values can be changed during operation dynamically, e.g. by a potentiometer on an
analog input. The speed override function does not affect the ramps set for accelera-
tion and deceleration. The function can be used, for example, for commissioning,
maintenance or in setup mode.
The signal source for adjusting the speed (e.g. analog multi-function input or fixed
percentage) is done via parameter
Reference Value Source 476.
Speed Override 1236
Function
0 - Off
Factory setting. Speed override disabled. Motion blocks
are processed at parameterized speeds.
1 - On
Speed override enabled. The speeds in the motion blocks
are set via the selected signal source.
The function does not change the speed in settings 10 to 24 (gearing) for parameter
Motion Mode 1208. The master speed is still applied. The function has to be acti-
vated on the master drive.
Note:
The travel speed is limited by the
Maximum frequency 419. The range
(limits for change of travel speed) is defined by
Min. Reference Per-
centage
518 and Max. Reference Percentage 519.
Example: The travel speed is controlled from 0 … 100% (0 … 10 V) via a reference
value potentiometer on multifunction input MFI1A. The percentages refer to the
speed values set in the motion blocks.
Power supply for reference value potentiometer via terminal X210B.5, ground to
terminal X210B.7
Reference value from potentiometer via multifunction input MFI1A, terminal
X210B.6
Multifunction input 1:
Parameter Operation mode 452 = "1 – Voltage Input"
Reference value via reference value channel: Parameter
Reference Percentage
Source
476 = "1 - Abs. Analog Value MFI1A"
Parameter
Minimum Reference Percentage 518 = 0.00% (factory setting)
Parameter
Maximum Reference Percentage 519 = 100.00% (factory setting)
Parameter
Speed Override 1236 = "1 - On"
Actual value parameter Reference Percentage 229 shows the specified travel speed
percentage.
+10 V/ 4 mA
MFI1A
GND 10 V
X210B
1
2
3
4
5
6
7
100%
Speed
1203
0%
S
p
eed
1203
(limited to )
M
aximum Frequency
419
Minimum Reference Percentage
= 0%
518
Maximum Reference Percentage
= 100%
519
=
=
Application manual Positioning 04/08104