TMCM-343 Hardware Manual (V1.07 / 2011-JUN-08)
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Copyright © 2011, TRINAMIC Motion Control GmbH & Co. KG
7.5
stallGuard™ - sensorless motor stall detection
The TMCM-343 modules are equipped with the stallGuard™ feature. The stallGuard™ feature makes it
possible to detect if the mechanical load on a stepper motor is too high or if the traveler has been
obstructed. The load value can be read using a TMCL™ command or the module can be programmed
so that the motor will be stopped automatically when it has been obstructed or the load has been
too high.
stallGuard™ can also be used for finding the reference position without the need for a reference
switch: Activate stallGuard™ and then let the traveler run against a mechanical obstacle that is placed
at the end of the way. When the motor has stopped it is definitely at the end of its way, and this
point can be used as the reference position.
For using stallGuard™ in an actual application, some manual tests should be done first, because the
stallGuard™ level depends upon the motor velocities and on the occurrence of resonances.
Mixed decay should be switched off while stallGuard is in use in order to get usable results.
Value
Description
0
stallGuard™ function is deactivated (default)
1… 7 Motor stops when stallGuard™ value is reached and position is not set zero.
Table 7.6: stallGuard™ parameter SAP 205
To activate the stallGuard™ feature use the TMCL™ command SAP 205 and set the stallGuard™
threshold value according to Table 7.6. The actual load value is given by GAP 206. The TMCL-IDE has
some tools which let you try out and adjust the stallGuard™ function in an easy way. They can be
found at
stallGuard™
in the
Setup
menu and are described in the following chapters. Please refer to
the TMCM-341/342/343 TMCL™ Firmware Manual for further information about working with TMCL-IDE.
7.5.1
stallGuard™ adjusting tool
The stallGuard™ adjusting tool helps to find the necessary motor
parameters when stallGuard™ is to be used. This function can only be
used when a module is connected that features stallGuard™. This is
checked when the stallGuard™ adjusting tool is selected in the
Setup
menu. After this has been successfully checked the stallGuard™
adjusting tool is displayed.
First, select the axis that is to be used in the
Motor
area. Now you can
enter a velocity and an acceleration value in the
Drive
area and then
click
Rotate Left
or
Rotate Right
. Clicking one of these buttons will
send the necessary commands to the module so that the motor starts
running. The red bar in the
stallGuard™
area on the right side of the
windows displays the actual load value. Use the slider to set the
stallGuard™ threshold value. If the load value reaches this value the
motor stops. Clicking the
Stop
button also stops the motor.
Figure 7.6: stallGuard™ adjusting tool
All commands necessary to set the values entered in this dialogue are displayed in the
Commands
area at the bottom of the window. There, they can be selected, copied and pasted into the TMCL™
editor.
