Rockwell Automation 25-COMM-E2P PowerFlex 25-COMM-E2P Dual-Port EtherNet/IP Adapter - Manual (Page 66)

66 Rockwell Automation Publication 520COM-UM003A-EN-E - June 2013
Chapter 5 Using the I/O
Using Datalinks A Datalink is a mechanism used by PowerFlex drives to transfer data to and from
the controller. Datalinks allow a drive parameter value to be read or written to
without using an Explicit Message. When enabled, each Datalink occupies one
16-bit word in a ControlLogix, CompactLogix, or MicroLogix controller.
The following rules apply when using PowerFlex 520-series drive Datalinks:
• Datalinks cannot be used with Multi-drive mode.
• The target of a Datalink can be any appropriate Host parameter. For
example, Host parameter P041 [Accel Time 1] can be the target of the
Dual-port EtherNet/IP adapter installed in the drive.
• The data passed through the drive’s Datalink mechanism is determined by
the settings of the following parameters:
–
Device Parameter 02 [DLs From Net Act]
– Device Parameter 03 [DLs To Net Act]
– Host parameters C161 [Opt Data In 1] through
C164 [Opt Data In 4]
– Host parameters C165 [Opt Data Out 1] through
C168 [Opt Data Out 4]
• When an I/O connection that includes Datalinks is active, those Datalinks
being used are locked and cannot be changed until that I/O connection
becomes idle or inactive.
• When you use a Datalink to change a value, the value is NOT written to
the Non-Volatile Storage (NVS). The value is stored in volatile memory
and lost when the drive loses power. Thus, use Datalinks when you need to
change a value of a parameter frequently.
Datalinks for PowerFlex 520-series drive peripherals (embedded EtherNet/IP
adapter on PowerFlex 525 drives only and option modules such as an encoder or
communication adapter) are locked when the peripheral has an I/O connection
with a controller. When a controller has an I/O connection to the drive, the drive
does not allow a reset to defaults, configuration download or anything else that
could change the makeup of the I/O connection in a running system. The I/O
connection with the controller must first be disabled to allow changes to the
respective Datalinks.
IMPORTANT There are several parameters in the drive that will override the start source and
speed reference command if enabled. For details on these parameters, see the
PowerFlex 525 drive’s user manual, publication
520-UM001 .
Attempting to write a negative value to the Speed Reference will result in the
drive ramping to maximum speed due to overflow, the direction of the drive
can only be controlled programmatically with the appropriate bits (bits 4 and
5) in the Command Word.
IMPORTANT A reset is always required after configuring Datalinks so that the
changes take effect.