Rockwell Automation 1757-SWKIT5000 ProcessLogix R500.1 Installation and Upgrade Guide - Manual (Page 256)

Publication 1757-IN500A-EN-P - September 2002
11-16 Performance and Capacity Specifications
1757-PLX52 to 1757-PLX52 Communications Performance per 1757-PLX52 50 ms 5 ms
Maximum Initiator Node Pull/Get Request Rate to all target nodes on ControlNet. 50 @ 100 ms
100 @ 200 ms
250 @ 500 ms
500 @ 1 sec
5 @ 10 ms
10 @ 20 ms
25 @ 50 ms
50 @ 100 ms
100 @ 200 ms
250 @ 500 ms
500 @ 1 sec
Maximum Initiator Node Pull/Get Request Rate to all target nodes on Ethernet.
(1) 250 @ 500 ms
500 @ 1 sec
250 @ 500 ms
500 @ 1 sec
Maximum Target Node response Rate to Pull/Get Requests from all initiator nodes. 500 PPS 500 PPS
Maximum Initiator Node Push/Store Request Rate to all target nodes.
(2) (3) 50 PPS 50 PPS
Maximum target node response rate to push/store Requests from all initiator nodes.
(3) 50 PPS 50 PPS
Number of remote 1757-PLX52s that a 1757-PLX52 can initiate a peer connection with.
Excludes Exchange peer to peer. 5 5
Number of remote 1757-PLX52s that a 1757-PLX52 can receive a peer connection from.
Excludes Exchange peer to peer. 5 5
1757-PLX52 to PLC – Peer-to-Peer Communications Capacity per 1757-PLX52 50 ms CEE 5 ms CEE
Maximum number of Exchange REQUEST blocks per 1757-PLX52 32 32
Maximum number of Exchange RESPONSE blocks per 1757-PLX52 32 32
Maximum number of target devices for REQUEST blocks per 1757-PLX52.
• 1 DHRIO Module only counts as 1 Target Device even when communicating with multiple
PLCs on either DH+ network
8 8
Maximum number of remote initializing devices for RESPONSE block data per 1757-PLX52. 8 8
Maximum number of DHRIO modules per 1757-PLX52 2 2 (local chassis
only)
(1) Because Ethernet is inherently a non-deterministic network, no guarantees can be made about the timely delivery of critical data packets. The support of TCP/IP Ethernet as
the Supervisory network in ProcessLogix does not preclude the customer to design and configure a mission critical control strategy based upon Ethernet.
Ethernet is not a deterministic network. Consider these factors before employing a mission critical control strategy: Ethernet is subject to collisions, deferred transmissions, and
other anomalies, which may delay the arrival of critical data packets
Internal testing has shown that under a full load condition, approximately 1 in 30,000 peer fetches arrive at a peer node at greater than twice the configured peer update rate.
(2) Currently the SCM Step and the PUSH block are the only block types that can initiate peer push/store requests for 1757-PLX52 to 1757-PLX52 peer communications.
(3) For Ethernet Supervisory LAN systems, the maximum store rate is 500 msec.
Table 11.K 1757-PLX52 Controller Communications Performance
1757-PLX52 Controller Communications Performance