Datalinks, Overload protection i – Rockwell Automation 20B PowerFlex 70, PowerFlex 700 Reference Manual User Manual
Page 67
Datalinks
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013
67
4.
Overload Protection I
2
T - This is a software feature that monitors the output
current over time and integrates per IT. The base protection is 110% for 1
minute or the equivalent I
2
T value (i.e. 150% for 3 seconds, etc.). If the IT
integrates to maximum, an F64 “Drive Overload” fault will occur. The
approximate integrated value can be monitored via the [Drive OL Count]
parameter.
5.
Heatsink Temperature Protection - The drive constantly monitors the
heatsink temperature. If the temperature exceeds the drive maximum, a
“Heatsink OvrTemp” fault will occur. The value is fixed by hardware at a
nominal value of 100 degrees C. This fault is generally not used for
overcurrent protection due to the thermal time constant of the heatsink. It is
an overload protection.
6.
).
Datalinks
A Datalink is one of the mechanisms used by PowerFlex drives to transfer data to
and from a programmable controller. Datalinks allow a parameter value to be
changed without using an Explicit Message or Block Transfer. Datalinks consist
of a pair of parameters that can be used independently for 16 bit transfers or in
conjunction for 32 bit transfers. Because each Datalink consists of a pair of
parameters, when enabled, each Datalink occupies two 16 or 32-bit words in
both the input and output image tables, depending on configuration. A user
enters a parameter number into the Datalink parameter. The value that is in the
corresponding output data table word in the controller is then transferred to the
parameter whose number has been placed in the Datalink parameter. The
following example demonstrates this concept. The object of the example is to
change Accel and Decel times “on the fly” under PLC control.
The user makes the following PowerFlex drive parameter settings:
Parameter 300 [Data In A1] = 140 (the parameter number of [Accel Time 1]
Parameter 301 [Data In A2] = 142 (the parameter number of [Decel Time 1]
Programmable
Controller
I/O Image Table
Remote I/O
Communication
Module
Adjustable Frequency
AC Drive
Block Transfer
Logic Command
Analog Reference
WORD 3
WORD 4
WORD 5
WORD 6
WORD 7
Output Image
Data In A1
Data In A2
Data Out A1
Data Out A2
300
301
310
311
Parameter/Number
Block Transfer
Logic Status
Analog Feedback
WORD 3
WORD 4
WORD 5
WORD 6
WORD 7
Input Image
Datalink A
Datalink A