Two s7 400 PLC for R-Redundancy on ethernet

Hello Eastern,

I haven't come across the term R-Redundancy but I think you mean warm standby (Software redundancy).

Eastern

for synchronize the redundant date I want to use Ethernet CP 443-5

CP 443-5 is a Profibus CP. If you intend to use Profibus then you should go for CP443-5 Extended (Not the basic one).
If you insist to go with Ethernet then you need CP443-1.

Eastern

In case of s7 400 PLC for R-Redundancy can we do the I/O Redundency,if possible please tell me the way, or by doing some program can we do that?

Redundant I/O's (Siemens library) works only with S7-400 H-Systems.
You can find more info about it in fault tolerant S7 manual (Look at edr's link).
However I/O redundancy in Siemens means some FBs and FCs that (Simply)
1- analyze diagnostic info to detect faulty channels or modules.
2- compare inputs to get the right value
3-write toredundant outputs (Analog outputs have some special manners).

So, you can write your own code for that but think about the time you will spend on writing a perfect code and the effect of it on CPU's performance.
It is far better to rely on RED_IO library. at least you will find support for it.

I always think that software redundancy can be a key player in the market if it's configured using S7-300 CPUs but it would get out of competition if it's done with S7-400.

Now, Siemens has introduced S7 412-3H to narrow the gap between software redundancy and hardware redundancy.
I recommend to take a look at the new 412-3H CPU.
I don't think there will be much price difference since you are going to use Ethernet CPs for redundant link.

Best regards.

H-H