X20 system modules • Motor controllers • X20SM1436
2032
X20 system User's Manual 3.10
4.25.7.15.5 Register of the Standard and SSDC function models
4.25.7.15.5.1 Configuration registers - General information
Stall threshold
Name:
ConfigOutput01
The SM module features integrated sensorless load measurement for the motor axis. This is especially useful for
detecting a "stall condition" (e.g. if the motor moves to the end point during a homing procedure). It cannot be used
for torque monitoring during dynamic movements.
With the "stall threshold" register, a threshold can be defined according to the motor load, and the module detects
a stall condition started at this threshold (see "Error status").
This threshold value must be determined on a case-by-case basis, since the results of the load measurement are
influenced by a variety of factors.
•
Motor speed: A higher speed results in higher measurement values
•
Speeds that cause motor resonances (which interfere with load measurement) are to be avoided
•
Motor accelerations that create a dynamic load (and also affect the measurement) should also be avoided
•
It is especially important to be aware that mixed decay mode must be disabled or optimized for reliable
stall detection (see "Mixed decay threshold")
The higher the load measurement value, the lower the load. That means: A stall condition is detected if the load
measurement value drops below the trigger threshold for stall detection.
Data type
Value
UINT
See bit structure.
Bit structure:
Bit
Description
Value
Information
0
Stall detection is disabled
1
Minimum sensitivity for stall detection
2 to 6
Setting the sensitivity of stall detection
0 - 2
Trigger threshold for stall detection
7
Maximum sensitivity for stall detection
3 - 15
Reserved
0
Holding current, rated current and maximum current
Name:
ConfigOutput03 (holding current)
ConfigOutput04 (rated current)
ConfigOutput05 (maximum current)
The holding current, nominal current and maximum current registers are used to configure the desired motor
current.
Reasonable values are:
•
Holding current < Nominal current < Maximum current
The motor's nominal current is entered in the nominal current register according to the motor's data sheet.
Register
Description
Nominal current
Current during normal operation
Maximum current
Should be selected if a higher motor torque is required briefly during acceleration
phases.
Holding current
The holding current should be used in situations when less torque is required
(e.g. at a standstill). This reduces the amount of heat generated by the motor.
Switching between preset current values (holding current, rated current, maximum current):
Function model
Switching between preset current values at runtime
Default
Using bits 14 and 15 in the registers Motor StepX
Standard with enabled SDC information
Using the register Motor current
Data type
Value
Unit
USINT
0 to 117
Percent of the module's rated current
•
100% corresponds to the rated current of the motor bridge power unit listed in the tech-
nical data
•
117% corresponds to the maximum current of the motor bridge power unit listed in the
technical data
