Siemens SIMATIC FM 453, Manual

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FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
In all operating modes except Control mode, the “servo enable” signal is re-
quired for the duration of every traversing movement, irrespective of the pa-
rameter definitions. If the controller enable is not detected or is deactivated
during the movement, the “servo enable missing” message is triggered (see
Table 11-5, Class 3/No. 61).
In all operating modes except Open-loop control mode, the “controller
ready” signal is required for the duration of every traversing movement when
the parameter is active (MD37.2). If the servo ready is not detected or is
deactivated during the movement, the “servo not ready” message is triggered
(see Table 11-5, Class 3/No. 62).
Phase current control (“Boost” or “PWM”)
Via the interface signal “Boost” or “PWM” (Pulse Width Modulation), phase
current control can be used to optimize the performance of the stepper motor.
The FM 453 implements these two functions via an output. This is done by
alternate machine data selection.
The active level of the signal can be parameterized.
Signal response:
Movement status Output signal “Boost” Output signal “PWM”
Idle inactive pulse duty factor per
MD 51
Acceleration/delay active static active
Constant travel inactive pulse duty factor per
MD 50
The following table shows you the available machine data for parameterizing
the function.
MD Designation Value/Meaning
37 Control signals
37.17 Boost active 0: Boost function not used
1: Boost function used Output signal
37.18 PWM active 0: PWM function not used
1: PWM function used
37.19 Boost/PWM inverted 0: Signal high active
1: Signal low active
48 Boost duration absolute 1 ... 1,000,000 ms
49 Boost duration relative 1 ... 100%
50 Phase current travel Pulse duty factor [%]
51 Phase current idle
see Section 5.3.1, Dependencies
Function, PWM The signal is generated as a 20 kHz frequency.
Boost function
The signal is monitored with reference to the maximum absolute and relative
active phase.
Optional Signals
for Step Drive
Description of Functions