Danfoss VLT Series Programming Manual page 41

Servo Drive Operation
The CAM is represented in an XML file, which contains the
following information:
•
Master scaling (optional)
•
Slave scaling (optional)
•
Control loop parameter (optional; both sets)
•
Following error settings (optional)
•
Basic cam or advanced cam definition
The CAM configuration consists of the following
information:
•
Cyclic/non-cyclic
•
Master absolute/relative
•
Slave absolute/ relative (only applicable for basic
CAM)
For general information about the format of an XML file,
see chapter 10.2 General XML Conventions.
When parsing a CAM profile, the servo drive checks the
format and the plausibility. The result is available in the
sub-indexes 3 and 4 of the same objects (see
chapter 7.14.4 Parameters: CAM Profile 1–8 (0x3810–0x3817)).
These sub-indexes contain detailed information about the
parsing state, error result, and more detailed information
for debugging.
The factor group (see chapter 2.3.2 Factor Group) is not
used in CAM mode. The velocity must be given as a
unitless factor between rotor angle and angle of guide
value. The acceleration must be given as velocity per
degree of guide value. A CAM profile is running based on
the guide value. This value always runs from 0 to 1. To
adjust this to the real application environment, it is
possible to specify a factor (master scaling) to reduce or
increase the value that is considered as a full cycle.
There are 2 possible CAM buffer layouts available:
•
8 CAM profiles
•
2 CAM profiles with more data
The CAM buffer layout can be selected in object 0x380F
(see chapter 7.14.1 Parameter: CAM Profile Memory Layout
(0x380F)). Carry out a power-cycle to activate the selection.
All nodes are non-signaling nodes. The axis does not
automatically signal if it passes a node. However, for
example for debugging purpose, it is possible to enable
this signaling for selected nodes.
NOTICE
The factor group (feed constant, gear ratio, and so on)
has no effect in CAM mode.
MG36D102
Programming Guide
Terminology
Name
CAM profile
CAM
CAM configuration
Basic CAM
Advanced CAM
CAM profile activation
request (Handshaking)
Change CAM immediate/
delayed
CAM profile activation
Full CAM
Danfoss A/S © 01/2017 All rights reserved.
Description
Consists of 1 CAM and 1 CAM
configuration. A valid CAM profile is
automatically stored in the servo
drive (maximum 8 CAM profiles).
XML file (basic CAM or advanced
CAM) containing the data points or
the nodes and segments.
Contains the following information:
- Cyclic/non-cyclic
- Master absolute/relative
- Slave absolute/relative
List of data points that describe the
relationship between the slave
position and the master position.
Describes the relationship between
the slave and the master based on
nodes, segments, actions, and exit
conditions.
Handshaking procedure with
Controlword and Statusword to
activate a valid CAM profile. This
does not necessarily mean that the
profile starts immediately. This
depends on the CAM configuration,
time of CAM activation request, and
so on.
In the Controlword there are 2
options for changing the CAM:
- Immediate: Abort the currently
running CAM and immediately
change to the new CAM.
- Delayed: The currently running
CAM profile finishes first before
the CAM is activated (see
Illustration 2.37).
All setpoints of the CAM profile are
calculated and the servo drive is
able to run the CAM profile. This
mainly contains the calculations for
blending.
A basic CAM that is defined with
the 1 st data point at guide value 0
and last data point at guide value
1. The CAM is defined over the
whole guide value cycle. Not
applicable for advanced CAM.
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