Can you help me ?

Dear Sir,
We are Executing Material Handling Project. Where i am using Idec PLC - Microsmart : FC5A-D32-K3 + 5 Exp.Modules.
In this there are 5 Hoppers. To Fill Each Hopper take approxi. 5 Min. To execute.
If Hopper-3 is Filling & Hopper – 5 is empty signal recived, then we have to store this hopper No.
So, After Filling of 3 rd Hopper, we can start Hopper-5 Fill.
There is a possibility For eg. If Hopper-3 Filling Started Before Complete of this, If we recive
Hopper-5 Low, Next Hopper-1 Low, Next Hopper-4 Low, Next Hopper-2 Low. Then we should store
This seq. So,
1.> After Completion of Hopper-3 Fill, We Should start Hopper-5 Fill
2.> After Completion of Hopper-5 Fill, We Should start Hopper-1 Fill
3.> After Completion of Hopper-1 Fill, We Should start Hopper-4 Fill
4.> After Completion of Hopper-4 Fill, We Should start Hopper-2 Fill
In above Seq, If Hopper-5 Filling is in process & we recived Hopper-3 is Empty, Then store
This & Execute Hopper-3 Fill After 4th Execution only. [ i.e Hopper-4 ] Because already Hopper-1 & Hopper-4
In Line.
I Think, for this operation i may use FIFOF or FIEX Instructions.
Kindly explain about this instruction in detail, how they are work etc ....
If Possible send me a demo program of FIFOF & FIEX This will help us.
If you feel any other alternative is possible then please guide & explain me.
Waiting for your help.
Thanking you, Waiting for your feedback for the same.
With Best Regards,
ISHWAR PATIL # +91 95610 84400
Annapurna Automation & Controls
Pune.

While I deal a lot with IDEC PLC's, I don't do much with hoppers.

Try here: http://www.cyberneticbe.com/forum/

They may be willing to fulfill your "requirements".

Stationmaster