S7 400H redundant with Redudant I/Os

Help is needed for Redundant i/o's to use in the program

i have Digital input modules in in 2 different ET200 redundant racks
Address of one module is 0...1 where as its redundant module address is
2...3

how can i use these inputs in the program will i have to make (OR) these redundant inputs.

------
I 0.0----! > !---= Q 4.0
! !
I 2.0----! !
------

O I 0.0
O I 2.0
= Q 4.0

Similarly how to use Analog io's

Short answer, no

You will need to drop in the proper FBs and FCs into the user program and in a couple other locations. See the redundant I/O example program you have from Siemens.

In HW config you have to configure which modules you want paired for the redundancy.

I would lay out my first racks (primary) with proper sequential addressing, then make the redundant start higher.

You are limited with Analog Inputs to using voltage only since the signal will be paralleled to the (2) modules. You can set up the tolerance stuff in HW config.

For Analog output, you must put diode across the output since again you are using (2) modules.

To answer your question, you will use I0.0 and behind the scenes the redundant I/O FB is checking I2.0 to make sure there isn't a discrepancy between the two inputs.

In expample i have seen that FB's are dropped in OB1. Do i need to drop theses FB's
only one time in OB1 ?
Also How these i/0's can be addressed in wincc By tags. Do i need 2 tags for both inputs
means one for I 0.0 and one for its redundant input I 2.0?

QayyumChaudry said:

In expample i have seen that FB's are dropped in OB1. Do i need to drop theses FB's
only one time in OB1 ?
Also How these i/0's can be addressed in wincc By tags. Do i need 2 tags for both inputs
means one for I 0.0 and one for its redundant input I 2.0?

Click to expand...

They go in multiple places, OB1, OB82, OB81 and a couple others I can't recall right now.

If you are using WinCC Flex (have not done a 400H & Red I/O in TIA) you need to build up a 'switcher' so in the event of a failure of your primary PLC you will establish comms with the secondary PLC. There are some elegant solutions to this on the Siemens support site.

The one I used has PLC_1 and PLC_2 and then you actually use connection PLC_12 and VB script does the switching for you.

With that being said, dynamically linking Step7 project to WinCC Flex tags isn't really possible since the connection you are using is PLC_12 and is artificial.

I have just built up the tags in Excel and imported into WinCC Flex. Not the greatest but it does work very well when executed properly.

But I have wincc 7.0 sp2. How can i address these i/o's in wincc 7
Or how can address them in PCS7