Siemens SIMATIC FM 452, Manual

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Machine Data and Cam Data
8-9
FM 452 Electronic Cam Controller
C79000-G7076-C452-04
Address Name Type Initial Value Comment
64.0
68.0
SSW_STRT
SSW_END
DINT
DINT
L# –100 000 000
L# 100 000 000
Start software limit switch
End software limit switch
Range:
– 1 000 000 000
m to 1 000 000 000 m
This axis data is only of significance with a linear axis.
The software limit switches are active when the FM 452 is synchronized. The range set by the software
end limit switch is known as the working range. The limits of the working range can be monitored by the
FM 452.
The start software limit switch (SLS) must always be less than the end software limit switch (SLE).
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
0 300
-100
Axis
ÈÈÈÈÈÈÈÈÈ
Working range
ÍÍÍÍÍ
ÍÍÍÍÍ
Encoder range Travel range
SLS SLE
Absolute encoder (SSI)
The FM 452 is synchronized after it has received a complete error-free frame. The software limit switches
are monitored from this point in time.
The absolute encoder which you use must at least cover the working range (from software limit switch
start to software limit switch end).
Incremental encoder and initiator
After starting up the FM 452, the axis is initially not synchronized. The software limit switches are only
monitored after synchronization.
Relationship: working range, encoder range, travel range
•
The “working range” is the range you specify for your task using the software limit switches.
•
The “encoder range” is the range covered by the encoder. With a linear axis, this is placed
symmetrically over the working range by the module; in other words, the module shifts the encoder
range so that the distances between the software limit switches and the ends of the encoder range
are the same (see figure).
•
The “travel range” is the range of values that can be processed by the FM 452. It is dependent on the
resolution.
The following rule applies:
Travel range
≥
encoder range
≥
working range
Address Name Type Initial Value Comment
80.0 HYS DINT L#0 Hysteresis:
Ranges:
0...65 535 [pul]
resolution [
m
/
pul
]
The range of values depends on the resolution
:
The maximum value that can be input is as follows:
– For linear axes: maximum input value <
¼
of the working range
– For rotary axes: maximum input value <
¼
of the rotary axis range