hi to all ,

i have two separate CPU 414-4h , the problem is When the rack is powered all  LED's of the CPU's are lit and remains litted , two CPU have a same error , i tried to update firmware but one of them not responding at all and all LED's continued lit during upgrade procedure ,in  another CPU ,all LED going off after 2 min and nothing happen afterward .

can any  friend's help me to solve this problem ? 

Hi,

Have a look at SIMATIC Fault-tolerant systems S7-400H under chapter "11.3 The operating states of the CPUs" / Special features at startup on the page 126.

I hope I could help!

thanks Microman for your reply , but as i told before , i use this two CPU separately  and not as redundant , this chapter explain fault in redundant system and switch over with master and stby cpu .

can this problem cause due to flash EPROM inside the cpu ?

abbassma

thanks Microman for your reply , but as i told before , i use this two CPU separately  and not as redundant , this chapter explain fault in redundant system and switch over with master and stby cpu .

can this problem cause due to flash EPROM inside the cpu ?

 Hi,

Really just a note to the side regarding to the comment above:

• Was the CPU in question operated as H-CPU before?
• Maybe have a look at SIMATIC Fault-tolerant systems S7-400H under "Stand-alone operation B"/Changing the operating mode of a fault-tolerant CPU page 422.
• As you mentioned EPROM. Just a quick read SIMATIC Fault-tolerant systems S7-400H under chapter "5.6 Using memory cards"/ FLASH card page 63.

Good Luck!

hi again , and thanks for quick reply .

i'm tested your suggestion ,first thing i replaced the rack and tried to upgrade firmware and second test was removing main rack from its i/o and testing it  by only , all above test not responding for my cpu .

are you have any suggestion ???