Momentum M1E MSTR Function Block May Freeze Operation for 3-5 Minutes



Goals and Symptoms

The purpose of this Resolution is to inform users of Momentum M1E processors and 171CBB97030 Processor/4-Port Switches, of a potential problem with the TCP/IP MSTR function block.

Facts and Changes

If two or more TCP/IP MSTR function blocks are programmed and active at the same time, the function block may freeze its operation for 3-5 minutes but recover on its own without user intervention.

Causes and Fixes

This issue is resolved by upgrading the PLC to the appropriate Exec version listed below.
Momentum M1E Processors

  • 984LL Exec version 1.28 or higher (171CCC96020, 171CCC96030, 171CCC96030, and 171CCC98030)
  • IEC Exec version 1.29 or higher (171CCC96020 and 171CCC96030)

171CBB97030 Processor/4-Port Switches (allows either IEC or 984LL Exec installation)
  • 984LL Exec version 1.03 or higher
  • IEC Exec version 1.05 or higher

Legacy KB System (APS) Data: RESL191634 V1.0, Originally authored by DaDz on 04/10/2008, Last Edited by DaDz on 04/10/2008
Related ranges: Modicon Momentum