Hi List,

I have a customer who is interested in a high speed Hot Backup solution using either Siemens S7-417-4H or the new S7-414-4H processors with a
redundant Profibus-DP I/O network using ET200M racks. Does anyone on the list have experience with this particular type of setup. What kind
of snags/problems have you run into? How well does it really work? What is a realistic transfer time we should expect? Have you noticed
any effect on processor thruput when the backup system is added? Any experience/comments would be greatly appreciated.

Robert D. Wagner, P.E.

 

Hello Robert,

If you could let me know your detailed requirement I could help you since have worked extensively in the same system.
You could mail me at "[email protected]", mailto:[email protected]

 

Robert,
Without more details
I only have some words of caution for you:
If you need to use Fiber, Double-check and double-check the Fiber for your I/O network. Depending upon your application the SIEMENS DOCUMENTATION can INCORRECTLY SPECIFY CABLES AND CONNECTORS for the system.
PS the cable our system (Redundant-FailSafe system or HF) required was Siemens proprietary, not stocked in the US and had an 8 week lead time from Germany. (Not something you like to hear when a deadline is looming).
Other than that one issue the systems has been great.
PSS- Double-check the fiber.

 

Robert,
I have had extensive experience of the S7-417-4H system and have found it to be perfect in fault-tolerant processes. Just a couple quirks to watch out for unless Siemens has resolved these in the latest version....
1. If Master=Unit(0) and Standby=Unit(1) and Master fails, Standby takes over, you physically take out Unit 0....you can't access the programming port through Unit 1
2. If you add hardware on a live system, the synchronisation of the two processors can be tricky (but possible)
2. If you intend to use Redconnect redundant WinCC OS Servers with your AS's then that's a whole new ball game!!

Email if you want more...

Regards,
Mark Oldfield

mailto:[email protected]