CIP Axis Attributes
Chapter 4
Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018
451
See also
Stopping and Braking Attributes
These are Motion Control Axis attributes associated with DC Bus control
including functionality to address both under-voltage and over-voltage conditions.
DC Bus Voltage
Usage
Access
T Data
Type
Default
Min
Max
Semantics of Values
Required - BD
Get/GSV
T REAL
-
-
-
Volts
Measured DC Bus Voltage. For inverters and DC Converter Types, the DC Bus
measured is an input to the device. For all other Converter Types, the DC Bus
measured is an output of the device.
Power Loss Action
Usage
Access
T Data
Type
Default
Min
Max
Semantics of Values
Optional - D
Set/SSV
USINT
1
-
-
Enumeration
0 = Continue (Ignore) (R)
1 = Coast Thru (R)
2 = Decel Regen (O)
3...127 = Reserved
128...255 = Vendor Specific
Set the reaction to a DC Bus under-voltage condition when the DC Bus drops
below a hard-coded threshold in the device or the configured Power Loss
Threshold. This provides a specific (configured) response to an incoming power
loss while the drive/motor is running.
A
Continue
action selection configures the drive to ignore the power loss
condition and continue to run for as long as possible. A Bus Undervoltage
exception may occur if the DC Bus Voltage falls below the Factory or User Limits.
Otherwise, operation will continue until the low voltage power supplies drop out.
There may be concerns operating the power structure below the point where the
gate drives start to lose power where this could possibly result in drive damage.
The Bus Undervoltage Exception Actions will be set accordingly.
A
Coast Thru
action selection configures the drive to zero the PWM output of
the drive while leaving the axis in the Running state. If the incoming power
returns before the timeout period, given by the Power Loss Time, the drive
automatically starts to control the motor again. If, however, the power doesn't
DC Bus Control Attributes