Welcome Guest! The IOSH forums are a free resource to both members and non-members. Login or register to use them

Postings made by forum users are personal opinions. IOSH is not responsible for the content or accuracy of any of the information contained in forum postings. Please carefully consider any advice you receive.

Notification

Icon
Error

Options
Go to last post Go to first unread
Admin  
#1 Posted : 20 July 2001 15:33:00(UTC)
Rank: Guest
Admin

Posted By Rob Waldie
We are currently at the start of a project to replace our control room.

The current control room comprises of MIMIC panels, it is proposed that the MIMIC will be completely replaced by VDU's. I am concerned that VDU's will not provide operators with an adequate overview of the process and the approach should be a combination of MIMICs and VDU's

Does anyone have views or experience of this causing safety problems ( especially in an emergency )
Admin  
#2 Posted : 21 July 2001 11:55:00(UTC)
Rank: Guest
Admin

Posted By Mike Charleston
Rob

The visitor's experience that I have of various onshore control rooms is that in effect, the VDU's do both jobs.

Essential mimic diagrams are reproduced on one/more VDU screen(s) and provide instant process data updating, just the same. The real benefit is that all those previous mimics which are only needed for a proportion of the operator's time can now be available on a VDU as/when necessary.

What's more, the computer software should be able to flash up an alarm from any mimic when it occurs - and each VDU operator should be able to log into that specific mimic for assessment and action.

Hope that helps

Mike
Admin  
#3 Posted : 22 July 2001 13:11:00(UTC)
Rank: Guest
Admin

Posted By David Allan
As an ex nuclear submarine manouvering room watchkeeper the need for effective graded alarms and accurately reproduced readings is obviously vital. The confusion following alarms and misread readings etc was a major contributing factor in the Three Mile Island incident and in the Kegworth Air Crash. Our training always focussed on key readings first, then if safe, deal with the rest.

I would obviously feel more comfortable with a combined (ie some direct reading meters for vital measurements/controls)approach for redundancy and verification purposes, but software developments have taken the VDU approach to new and sophisticated levels. The need for continuing power supplies to allow VDU function would worry me and what about fire/emergency evacuation of the control room?

The only way to be sure is to conduct a full appraisal using, HAZOP, ETA, FMEA etc, not forgetting the ergonomic requirements of the panels and the operators.

Hope this helps,

David
Admin  
#4 Posted : 23 July 2001 16:24:00(UTC)
Rank: Guest
Admin

Posted By Phil Roberts
Rob, In my previous life I was a control room operator in the petrochemical industry and have experience of changing from a mimic panel to a computer/VDU panel. The changover did lead to some problems with not having an overall view and in one instance led to a serious flareing incident causing damage to a flare line. This was due to an operator opening a line into an already full vessel causing a high pressure thus opening a full LPG vessel to flare. After this incident an extra system was put in place with a VDU giving a rolling overview of the mimic type system with an immediate display of any deviation alarm. This combined with the computer control system was an improvement on the old mimic system and once familiar with the system was much easier to operate. Hope this gives some food for thought, Regards Phil
Admin  
#5 Posted : 30 July 2001 01:18:00(UTC)
Rank: Guest
Admin

Posted By Roy Macpherson
Rob
The control room at our power station has a mix of VDU based displays and mimic panels for indications for all of our plant. In most cases the VDU system updates the system condition much faster than the mimic displays and is more accurate in its display of process systems. It also allows for much more data to be available to the operators which in normal circumstances is great. The major problem however is the loss of power supplies, this has in the past led to some extremely interesting situations-we lost all power at 3am and the backup power supplies which were supposed to last for 8 hrs in fact crashed after 20 mins. Fortunately all the systems are failsafe and the units rolled to a stop safely but without the indication on the VDU's we had to rely on what information came back to us through the old analogue instrumentation. Not an ideal situation and one that caused a massive upgrade of backup power supplies. Another thing to be careful of is touch sensitive screens, they are very useful but I have seen a whole batch of product trashed by thoughtless finger poking on a touch screen by an electrician tracing a system and tapping on the screen to make his point to the operator!
Users browsing this topic
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.