Re: [foxboro] Foxboro SIL Rating


We generally use a separate, TUV-approved programmable safety system (PES
in ISA S84 terminology) for these applications.  Where the I/A must use
inputs that go to the PES, we repeat the signals via outputs for
control/interlock loops, with some multiplexed data transfer (Modbus
serial, Ethernet, native DCS network interfaces) for non-critical data.
Except in a few isolated cases (e.g., turbomachinery controls), S84
requires the separation of the control system and the safety system.   I
suspect IEC 61508/61511 has similar requirements.

Corey





"Ghodhbani, Hafedh" <hafedh.ghodhbani@xxxxxxxxxxxx>@freelists.org on
04/28/2002 06:14:53 AM

Please respond to foxboro@xxxxxxxxxxxxx

Sent by:    foxboro-bounce@xxxxxxxxxxxxx

To:    Foxboro
cc:
Subject:    [foxboro] Foxboro SIL Rating



Gents,
As we all know, the Foxboro system is not certified for
any SIL (Safety Integrity Level) rating. This means that : If we would like
that our safety functions are SIL rated, so a new certified ESD System is
to
be installed.
Foxboro system needs to be used only for control logic.
The above situation generated long discussions, essentially when SIL study
was carried out for new plant extention.
I am very concerned to know if you faced such situation. How did you dealt
with it?

Note: To know more about SIL Rating, see IEC 61508.


Hafedh Ghodhbani
Senior C&I Engineer
British Gas.
Tel: 00 216 74 259 250

______________________________________________________________________
BG Energy Holdings Limited (a member of BG Group)
Registered in England No: 3763515
Registered Address:
   100 Thames Valley Park Drive
   Reading
   Berkshire   RG6 1PT   UK
Telephone:        +44 (0) 118 935 3222
Website:          http://www.BG-Group.com

This e-mail is intended only for the addressee named above.  As this
e-mail may contain confidential or privileged information, please
advise us immediately if you are not the named addressee or the person
responsible for delivering the message to the named addressee.  The
contents should not be disclosed to any other person nor copies taken.
______________________________________________________________________


_______________________________________________________________________
This mailing list is neither sponsored nor endorsed by Invensys Process
Systems (formerly The Foxboro Company). Use the info you obtain here at
your own risks. Read http://www.thecassandraproject.org/disclaimer.html

foxboro mailing list:             http://www.freelists.org/list/foxboro
to subscribe:         mailto:foxboro-request@xxxxxxxxxxxxx?subject=join
to unsubscribe:      mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave





 
 
_______________________________________________________________________
This mailing list is neither sponsored nor endorsed by Invensys Process
Systems (formerly The Foxboro Company). Use the info you obtain here at
your own risks. Read http://www.thecassandraproject.org/disclaimer.html
 
foxboro mailing list:             http://www.freelists.org/list/foxboro
to subscribe:         mailto:foxboro-request@xxxxxxxxxxxxx?subject=join
to unsubscribe:      mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave

Other related posts: