Honeywell Experion DCS Redundant Analog Output Card Failure...

H

Thread Starter

hatimnazir

Recently a issue was faced that one I/O Module which was Redundant Analog Output Module failed and all the outputs went to initialization states.

We checked from the DCS Server station, and found the points analog output blocks gone inactive. We then activated the blocks one by one to restore it back. Later we also found that soft AO configuration was also changed as some of the valve were opened in field and DCS was showing 0% so we had to change action again to "reverse".

Please help me out what can be the cause of the AO card failure?
Why the point Analog Output block went to inactive state?
Why the action changed for some valves in configuration?

Please help me out what can be the cause of the failure of the AO module?
 
H
Apart from this, the DCS event also shows the following:
"IOM (input output module) switch over to Power ON"
Note: during this incident of Card failure there was a job going on one Control Valve which was terminated on the same Analog Output card.

Please help me out what can be the cause of IOM Power ON?
 
T
Similar problem we had faced in Honeywell EPKS 300 system and also recently upgraded to EPKS 400.

Detail of same is written bellow.
(1) Incident-01: (CP3 :In Year 2010 to 2011) : AO module soft fail alarm observed ( No response,all channel inactive),On Power resetting, IOP module found working ok for three to four days and again it failed and problem repeated. Replaced AO IOP module and FTA with Cables and IOP redundancy provided. Again Master AO IOP failure observed three four times, every time secondary took over. hence it was confirmed that the FTA is problematic, FTA was replaced, Redundancy removed and removed FTA was sent to Honeywell for detail analysis but no problem reported in module. Removed FTA installed in less critical area and now working without any problem but reason of such behavior and IOP failure reported is not clear and not concluded?

2) Incident:2 (CP1, In Year 2013 ) : Redundant Master IOP failure observed ( No response) and tookover by Redundant one, spares IOPs installed but same problem repeated for new IOPS and redundant location too at interval of 3 to 4 month, FTA is replaced in April 2014 plant shutdown time and IOP is working ok.

3)Incident 3: ( CP2 Date 29/04/2014) : Plant tripped twice due to non redundent AO IOP failure ( No response), IOP replaced but again IOP failed to No response on next day so FTA was replaced but after three days again IOP failed. AO IOP made Redundant, FTA Cable and again FTA card replaced.

In above mentioned failures, system has never given FTA failure message but always have given IOP No response status, which later on IOP and FTA have found working ok.

Also During last failure it was observed that initially two channel Bad status (bad control) alarm was coming and after 10 seconds AO IOP NO RESPONSE was coming but field loop condition for both tags were checked and found ok.

As discussed with Honeywell engineer , there is no proper logical reply for such type of failure.

Our observations are that

(1) All three CP have observed similar problem.So there is no backplane (hardware failure related problem.). Also same modules (IOP and FTA) works ok in other slots.

(2) Problem has been observed in EPKS 300 and latest EPKS 400 version.

(3) In all above three cases, no barriers are used and there is no problem in field wiring/loop/earthing or open shorts.

Can some experienced member give proper response?

Thanks.
T.M. Vekaria


 
Similar problem we had faced in Honeywell EPKS 300 system and also recently upgraded to EPKS 400.

Detail of same is written bellow.
(1) Incident-01: (CP3 :In Year 2010 to 2011) : AO module soft fail alarm observed ( No response,all channel inactive),On Power resetting, IOP module found working ok for three to four days and again it failed and problem repeated. Replaced AO IOP module and FTA with Cables and IOP redundancy provided. Again Master AO IOP failure observed three four times, every time secondary took over. hence it was confirmed that the FTA is problematic, FTA was replaced, Redundancy removed and removed FTA was sent to Honeywell for detail analysis but no problem reported in module. Removed FTA installed in less critical area and now working without any problem but reason of such behavior and IOP failure reported is not clear and not concluded?

2) Incident:2 (CP1, In Year 2013 ) : Redundant Master IOP failure observed ( No response) and tookover by Redundant one, spares IOPs installed but same problem repeated for new IOPS and redundant location too at interval of 3 to 4 month, FTA is replaced in April 2014 plant shutdown time and IOP is working ok.

3)Incident 3: ( CP2 Date 29/04/2014) : Plant tripped twice due to non redundent AO IOP failure ( No response), IOP replaced but again IOP failed to No response on next day so FTA was replaced but after three days again IOP failed. AO IOP made Redundant, FTA Cable and again FTA card replaced.

In above mentioned failures, system has never given FTA failure message but always have given IOP No response status, which later on IOP and FTA have found working ok.

Also During last failure it was observed that initially two channel Bad status (bad control) alarm was coming and after 10 seconds AO IOP NO RESPONSE was coming but field loop condition for both tags were checked and found ok.

As discussed with Honeywell engineer , there is no proper logical reply for such type of failure.

Our observations are that

(1) All three CP have observed similar problem.So there is no backplane (hardware failure related problem.). Also same modules (IOP and FTA) works ok in other slots.

(2) Problem has been observed in EPKS 300 and latest EPKS 400 version.

(3) In all above three cases, no barriers are used and there is no problem in field wiring/loop/earthing or open shorts.

Can some experienced member give proper response?

Thanks.
T.M. Vekaria
Did you find the root cause for this problem?
 
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