Nigel, We run our carbon furnace via integrated Foxboro / Allen-Bradley. We do it with an AB30 gateway -- 19.2Kbaud KF2 -- Allen Bradley ControLogix 5500. (Since our ControLogix has to emulate a PLC5 for the communications to work, there is no real difference from what you have.) Since the BMS is written well enough to be self-contained we really need the integration mostly for the graphic user interface. But, there are a few loops (mostly temperatures, I think) that we monitor in the I/A for alarm conditions. We OR the I/A alarms and pass a single Boolean value back to the PLC for a shutdown on any of these conditions. Anything that needs a response time of less than two seconds is monitored in the PLC, because the KF2 limits our AB30 gateway to a two second scan time. We do two things for peace of mind. We have a "heart beat" continually passing between the two systems to ensure we have communication. We also monitor the position of the PROG-RUN-REM_RUN key switch via the gateway. =20 PROS: The PLC BMS is certified. The I/O and wiring were cheaper. The BMS was stand-alone, in the end it was not much different than operating a valve or motor from the I/A. CONS: The gateway communications are slow. Any time you have more than one control system controlling one piece of equipment, it is a negative. We have not had a problem with it since we put it in four years ago. Chuck Jones Automation Technologist Tate & Lyle -- Lafayette South Plant 765.477.5324 - Office | 765.586.5290 - Cell -----Original Message----- From: foxboro-bounce@xxxxxxxxxxxxx [mailto:foxboro-bounce@xxxxxxxxxxxxx] On Behalf Of Baptiste, Nigel Sent: Friday, March 31, 2006 7:50 AM To: foxboro@xxxxxxxxxxxxx Subject: [foxboro] Integration or replacement of AB PLC5 BMS? Hello List, At our plant we are considering a boiler control upgrade and the BCS =3D would be upgraded to the Fox I/A. However, the BMS is an AB PLC5 system =3D and the decision to be made is whether to replace it and implement in =3D I/A system or use an integrator. Does anyone have experiences with this sort of integration? What are the pros/cons. Cost would be a factor in the decision making process - however, =3D reliability is key. Regards, NB. =20 =20 _______________________________________________________________________ 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 =20 foxboro mailing list: //www.freelists.org/list/foxboro to subscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=3Djoin to unsubscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=3Dleave =20 ***************************************************************************= ************************** This email and any files transmitted with it are confidential and intended = solely for the=20 use of the individual or entity to whom they are addressed. If you are not = the intended=20 recipient or the person responsible for delivering the email to the intende= d recipient, be=20 advised that you have received this email in error that any use, disseminat= ion,=20 forwarding, printing, or copying of this email is strictly prohibited. If = you have received=20 this email in error please notify the sender immediately. Please note that = we reserve=20 the right to monitor and read any emails sent and received by the Company i= n=20 accordance with and to the extent permitted by applicable legal rules. ***************************************************************************= ************************** _______________________________________________________________________ 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: //www.freelists.org/list/foxboro to subscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=join to unsubscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave