Allen-Bradley 22-COMM-E FRN 1.xxx User Manual page 62

7-2 Using Multi-Drive Mode
Figure 7.2 Multi-Drive Mode Example for Network
EtherNet/IP
PowerFlex 40
AK-U0-RJ45-TB2P
Connector with
Terminating Resistor
Benefits of Multi-Drive mode include:
• Lower hardware costs. Only one 22-COMM-E adapter is needed for
up to five drives. PowerFlex 4's can also be used for the daisy-chained
drives instead of PowerFlex 40's.
• Reduces the network node count. For example, in Single mode 30
drives would consume 30 nodes. In Multi-Drive mode, 30 drives can be
connected in 6 nodes.
• Provides a means to put PowerFlex 4's on EtherNet/IP (PowerFlex 4's
do not have an internal communications adapter slot).
• Controller can control, monitor, and read/write parameters for all five
drives.
The trade-offs of Multi-Drive mode include:
• If the PowerFlex 40 with the 22-COMM-E 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
mode). This is because the 22-COMM-E 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:
Drive
PowerFlex 40 with 22-COMM-E
PowerFlex 40 with 22-COMM-E plus 1 drive
PowerFlex 40 with 22-COMM-E plus 2 drives
PowerFlex 40 with 22-COMM-E plus 3 drives
PowerFlex 40 with 22-COMM-E plus 4 drives
up to 5 drives per node
Up to 4 PowerFlex 4's or 40's
22-COMM-E
RS-485 AK-U0-RJ45-TB2P
Additional Throughput Time
versus Single Mode
0 ms
+24 ms
+48 ms
+72 ms
+96 ms
AK-U0-RJ45-TB2P
Connector with
Terminating Resistor