Siemens SINUMERIK 802S Technical Manual page 77

Rotation monitoring of the stepper motor using BERO
Overview
Machine data
Activation
Error case
SINUMERIK 802S base line
Start-Up
Servo Enable
z
Positioning measuring system ON/OFF
z
Parking
z
Error responses
z
It is the user's own responsibility to cause the PLC that the appropriate stepper
motor drive is brought to "Safe Stop" or is switched off.
A stepper motor will no longer follow the setpoint if the load torque becomes
too large. The rotation monitoring is intended to detect this faulty status.
At the moment when the BERO pulse occurs, the stepper motor setpoint
position is compared with the BERO actual position and, in case of error, the
"Error: Rotation monitoring signal" is created.
The rotation monitoring BERO must be overrun cyclically when the axes are
traversed. Usually, a cyclically occurring BERO is used both referencing and
for rotation monitoring.
It is possible to switch the BERO for rotation monitoring in parallel to the BERO
for referencing. It must, however, be made sure that the rotation monitoring is
disabled when referencing and that the rotation monitoring BERO does not
provide a signal or the referencing BERO is switched off when rotation
monitoring is active.
The MD 31100 BERO_CYCLE must contain the repetition cycle of the BERO in
actual-value increments. The MD 31110 BERO_EDGE_TOL will take into
account any tolerances in the BERO switching edge.
The speed monitoring is activated via the user interface signal 380x5000.0. It
comes into effect for the appropriate axis only after referencing.
The error "Rotation monitoring" is signalled (interface signal 390x5000.0) and
the monitoring is switched off. The reference point is lost. To re-enable rotation
monitoring, rereferencing is required.
Notice
The error "Rotation monitoring" will also always occur if the stepper motor has
been controlled incorrectly even if the speed monitoring is not enabled. If
deemed necessary, the user must take appropriate measures to ensure that
the stepper motor is shut down reliably.
Start-Up
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