Multi-drive mode – Rockwell Automation 25B PowerFlex 525 Embedded EtherNet/IP Adapter User Manual
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Rockwell Automation Publication 520COM-UM001B-EN-E - March 2013
Chapter 7
Using Multi-Drive Mode
Multi-Drive Mode Example for Network
Benefits of Multi-drive mode include:
•
Lower hardware costs. No need to purchase additional communication
adapters for daisy-chained drives.
•
Reduces the network node count. For example, in Single-drive mode 30
drives would consume 30 nodes. In Multi-drive mode, 30 drives can be
connected in 6 nodes.
•
Controller can control, monitor, and read/write parameters for all five
drives.
The trade-offs of Multi-drive mode include:
•
If the PowerFlex 525 with embedded EtherNet/IP adapter is powered
down, then communications with the daisy-chained drives is disrupted
and the drives will take the appropriate communications loss action set in
each drive.
•
Communications throughput to the daisy-chained drives will be slower
than if each drive was a separate node on EtherNet/IP (Single-drive
mode). This is because the embedded EtherNet/IP adapter must take the
EtherNet/IP data for the other drives and sequentially send the respective
data to each drive over RS-485. The approximate additional throughput
time for Logic Command/Reference to be transmitted and received by
each drive is:
IMPORTANT
For the examples in the chapter, we will use the PowerFlex 525 as a master
drive with four daisy-chained PowerFlex 4M drives.
Drive
Additional Throughput Time
versus Single-Drive Mode
PowerFlex 525
0 ms
PowerFlex 525 plus 1 drive
+24 ms
PowerFlex 525 plus 2 drives
+48 ms
PowerFlex 525 plus 3 drives
+72 ms
PowerFlex 525 plus 4 drives
+96 ms
Esc
Sel
Up to 5 drives per node
EtherNet/IP
Up to four daisy-chained PowerFlex drives
(PowerFlex 4M shown)
RS-485 cable
PowerFlex 525
as master drive
AK-U0-RJ45-TB2P connector with
terminating resistor (120
Ω
)
AK-U0-RJ45-TB2P connector with
terminating resistor (120
Ω
)
AK-U0-RJ45-TB2P