PLC414H系统故障描述

0号机架上的CPU 死机，所有的灯都闪，CPU重启无效，关掉电源再重启后恢复，但过几天又出现上述故障现象。此现象是2007年5月18日首次出现，到现在已多次发生，影响到我厂的安全生产，请各位帮忙解决。
以下是截取的6条诊断信息：
Module Information -CPU 414-4 H "Diagnostic Buffer" Tab

Settings:
 Time including CPU/Local time difference(0 h)

Event 104 of 120: Event ID 16# 7301
Loss of redundancy (2oo2) due to CPU failure
CPU affected:Standby CPU in rack 0
Event: Standby CPU : Change from redundant mode to error-search mode
Requested OB: CPU redundancy error OB (OB72)
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Event 103 of 120: Event ID 16# 45E4
Standby CPU : Change from redundant mode to error-search mode
Error-search mode :trigger event: 43D8:Error-search mode : Hardware error detected due to other error
FC number :110
Moudle address: 1220
Event occured in the standby CPU in rack 0
。。。。。。
Event 100  of 120: Event ID 16# 5371
Distributed I/Os: end of the synchronization with a DP master
Slot of the DP master:4 in rack 0
Number of distributed stations: 8
Event occured in the standby CPU in rack 0
。。。。。。。。。。
Event 84 of 120: Event ID 16# 7955
SYNC submodule error
occured in : Master CPU in rack 1, no relevance for USER : 01
Submodule affected: Upper SYNC submodule (IFM1F)
Requested OB : CPU redundancy error OB (OB72)
External error, Incoming event
。。。。。。。。。。。。。
Event 78 of 120: Event ID 16# 7855
SYNC submodule error eliminated
occured in : Master CPU in rack 1, no relevance for USER : bb
Submodule affected: Upper submodule (IFM1F)
Requested OB : redundancy error OB (OB72)
External error, Incoming event
。。。。。。。。。。。。。
Event 106 of 120: Event ID 16# 6981
Interface error entering state
Interface ID : X1,MPI/DP
Event occurred in the standby CPU in rack 0
External error, Incoming enent