9.3 Switch-On and Switch-Off Behavior
This chapter describes the switch-on and switch-off behavior of the AKD2G with STO.
Behavior of “holding brake” function
Drives with an enabled holding brake function have a special timing for switching on and off
the output stage (
# 84). Events that remove the AXIS#.ACTIVE signal trigger the holding
brake to apply. As with all electronic circuits, the general rule applies that there is a pos-
sibility of the internal holding brake module failing.
If the drive detects the motor to be at zero velocity (as configured by AXIS#.ZEROT and
AXIS#.ZEROV) or timeout occurs during a stop procedure, the brake is applied. Set para-
meter AXIS#.MOTOR.BRAKEIMM to 1 with vertical axes, to apply the motor holding brake
(
# 84) immediately after faults or Hardware Disable.
Behavior when undervoltage condition is present
The behavior in an undervoltage condition depends on the VBUS.UVMODE setting.
VBUS.UVMODE
DC Bus Undervoltage Mode. Consult the WorkBench Online Help for
configuring the parameter.
0
The drive will report a F2007 undervoltage fault any time an under-
voltage condition occurs.
1 (default)
The drive will report a warning W2007 if not enabled. The drive will
report a fault if the drive is enabled when the condition occurs, or an
attempt is made to enable while an under voltage condition occurs.
Functional Safety
The drive can be secured to standstill with STO. Even when power is being supplied, the
drive shaft is protected against unintentional restart. The chapter “Functional Safety”
describes how to use the safety functions (
Functional safety, e.g. with hanging load (vertical axes), requires an additional brake, con-
trolled for example from the second axis or externally from a safety controller. The brakes
can be mapped to an axis with WorkBench.
The Hardware Enable does not initiate a controlled stop but switches off the power stage
immediately.
Set parameter AXIS#.MOTOR.BRAKEIMM to 1 with vertical axes, to apply the brake
immediately after faults or Hardware Disable.
AKD2G-S Installation Manual, Safety 1 | 9 Setup
Kollmorgen | kdn.kollmorgen.com | July 2020
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