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What is the total number of Modbus TCP/IP messages that can be processed by the Quantum PLC's each scan (cycle)?

The following table shows the total number of Modbus TCP/IP messages that can be processed by the Quantum PLC's
each scan per the number of communication (NOE) modules in the system.


msg/cycle: number of messages being received per cycle from the PLC master task (typical cycle from 50 to 100 ms).

(1) Only if using Unity Pro software. If using PW or Concept then:
All Comm requests = 1 msg/cycle
Additional 4x = 4 msg/cycle
Ethernet Modules per PLC still = 6, however only 2 are looked at per PLC scan.

For Example if you had a 140CPU43412 with 4 140NOE77101's programmed with Unity Pro then the total number of msg/cycle is:
For All types of Communication
4 x 4 msg/cycle = 16 msg/cycle
For read/write 4x registers
4 x 8 msg/cycle = 32 msg/cycle


Legacy KB System (APS) Data: RESL187028 V2.0, Originally authored by MiMe on 07/12/2007, Last Edited by MiMe on 05/15/2008
Related ranges: Modicon Quantum
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