lolol.. I hope that they have more responsible people running your nuke plants than they have here running ours....
Did you see the documentary of PA? It is unbelievable that so many mistakes and situations happened consecutively.
Luckely, because of PA, all our procedures and reactions on...
Yip, We have tripple transmitters for two out of three voting on critical ESD systems, wired to the ESD PLC.
So my system will be:- a process diversion valve(XV) on each line, with one ESD valve upstream and common to both batch process diversion valves(XV's).
This project is an expansion on...
Sir,
You misunderstand.
I meant with (ESD-type)that it is on/off process valve with ESDV specs. No backup.
The normal operation is with XV doing the normal process operations AND the ESDV is in the open position, (fail close), giving the redundant backup. So if the Conrol or on/off valve...
MMmmmmm,
Very interesting oppinions.
Mr. dcasto, as you say: "It says each device will have its own wiring to the I/O of the controller"
The plant I am designing, has two seperate systems already. a PLC ESD and a DCS control system. As I understand it, if you wire the valve to the ESD...
Gentlemen,
Thank u very much, fellow engineers, for your interest and comments on my post.
Geeeeeeeeeeeeeeez, lolol... I read and read and read code after spec after report.
I understand the rules as: Seperate control system for ESD and seperate control system for process control. Therefore...
Thanks David,
In all my designs I have never done this either. I have a client that wants to do this and I cannot, for the life of me, find any code stating that you are not allowed to do this. API only tells me that: ESD equipment must be additional and independent to the normal process. So...
Fellow Engineers,
Are you allowed to use an ESDV (ESDV spec.valve) for both functions, i.e. as a normal operating valve and as an ESDV? (e.g. two solenoids in series on the supply, one driven by the normal control system and on by the ESD system)
Regards
Pieter
