Bailey Network 90

Hello, we have a Bailey Net90 system used for BMS on a boiler. We’ve encountered issues with header valves cycling open and closed while the boiler is running. We have 4 burners on this boiler and the valves cycled with 2 burners on and 4 burners on etc. We ran the boiler and had a rep come in to diagnose and saw no issues.The issues have occurred on the off hour while we were not present. Has anyone encountered and issues with this? We are suspecting output boards (for 110 VAC rated solenoids). It’s hard to troubleshoot when all looks healthy out in the field. Weather wise the problems occurred on dry days, no rain.
We’ve replaced output boards and rep performed resets on the individual burners and header logic boards.
 
Hello, we have a Bailey Net90 system used for BMS on a boiler. We’ve encountered issues with header valves cycling open and closed while the boiler is running. We have 4 burners on this boiler and the valves cycled with 2 burners on and 4 burners on etc. We ran the boiler and had a rep come in to diagnose and saw no issues.The issues have occurred on the off hour while we were not present. Has anyone encountered and issues with this? We are suspecting output boards (for 110 VAC rated solenoids). It’s hard to troubleshoot when all looks healthy out in the field. Weather wise the problems occurred on dry days, no rain.
We’ve replaced output boards and rep performed resets on the individual burners and header logic boards.
Hello Asabula,

There is some misunderstanding, of the issue you try to describe.

We do not know what kind, of "fault" or "error message" that the system is eventually displaying.

Also if you could share, a schematic it would be helpful to get better overview .

What are the results after:
1-Replacing output board
2-Resetting individual burner
3-Ressetting header logic boards??

Can you explain the term "resetting " as it can be a general term.

With kind of datas you provided, we are like swimming in dark/troubled water.

Thank you for your reply,
Controlsguy25.
 
Hello thanks for the response. The header valves start cycling so quickly that no alarms get generated. As a safety precaution the operators would initiate a trip shortly after.
By resetting, what I mean is the rep performs a logic board reset from the laptop that is connected to the system.
By replacing the output board the corresponding LED on the module that trips our main header valve would go out. LED ON for this valve commands it closed. Resetting the header logic and individual burner logic boards did not really do anything for us as it was that night afterwards where the valves started opening and closing again on their own while the boiler was online. We are suspecting the output board to be faulty but cannot tell for sure as the cycling has not been witnessed by us while we were on site. Unfortunately I cannot provide a schematic due to work privacy protocols.
Just a note, the output boards that we have been replacing are ones that have already been here, we have not purchased any new output boards.
 
Hello thanks for the response. The header valves start cycling so quickly that no alarms get generated. As a safety precaution the operators would initiate a trip shortly after.
By resetting, what I mean is the rep performs a logic board reset from the laptop that is connected to the system.
By replacing the output board the corresponding LED on the module that trips our main header valve would go out. LED ON for this valve commands it closed. Resetting the header logic and individual burner logic boards did not really do anything for us as it was that night afterwards where the valves started opening and closing again on their own while the boiler was online. We are suspecting the output board to be faulty but cannot tell for sure as the cycling has not been witnessed by us while we were on site. Unfortunately I cannot provide a schematic due to work privacy protocols.
Just a note, the output boards that we have been replacing are ones that have already been here, we have not purchased any new output boards.
Thank you for answering.

Well It would be difficult to perform, such troubleshooting remotely from here and without datas/informations .

Resetting logic board, without knowing reason/cause of the "Issue", is not good at all!

Is that module is coming, with Master fuel trip or over equipment? Are you able to open close the valves ("manually or automatic" from DCS) ?
If yes what is the behaviour?

Ok I understood that you cannot provide schematic, but without knowing module reference/type OEM we cannot give you advices.

Seems that valves are closing/opening fast?? Is there any incidence on the process??

I can check with people around my professionnal network if somebody have been faced to kind of issue .

Also , are you referring to the modulating throttling valve?
 
The Bailey is strictly BMS. Only opens and closes SSOV’s. Strictly open and close. Our Honeywell controls throttling valves such as air flow, fuel gas etc. Control from that point is checked out just fine. There is a MFT relay that checks out ok as well while we are here. We were hoping to see the cycling issues to see if it was the MFT relay chattering but it stays steady. We can only open the individual valves from the Bailey and they cannot open and close individual valves from the control room. When we stroke the valves from the Bailey laptop they work perfect.
The information tag on the output card states: NDSM05 Network 90, Digital Slave Module, 24VDC. Sticker on the card has a number 010006-068.
 
Asabula,
Have you checked the Event Historian to see if any commands came from the DCS? If any commands were sent via logic or operator actions, it should show up here (from any control screen click Select>Event Historian). The only other thing I could think of real quick would be maybe some induced (stray) voltage from another source into the control circuit. I've seen that many times in 24VDC control circuits.

Hope you figure it out soon,
RichT1
 
RichT1, I will get the rep to check the historian. We finally were able to witness the valve command chatter. All the commands on that specific cable were ok except the one in question which ruled out stray voltage. We found a solid state relay that had an issue and replaced it which helped out the issue. We are going to try a light off tomorrow and see how it goes.
we also have a data logger connected to the outputs to the main header valves so we can check in the morning if it saw any voltage spikes. Thanks for the tip on the historian. We will keep you guys posted.
 
All,
As a summary, since the system is old they are thinking we have backplane issues since so many odd things were going on with valve output cycling, board issues, random alarms etc. We have the boiler lit finally and they are going to propose an upgrade with a new backplane and new boards. The boiler is having a schedule outage later this year and we will look into the upgrade if that is the route they go. Thank you all for the tips and take care of yourselves.
 
All,
As a summary, since the system is old they are thinking we have backplane issues since so many odd things were going on with valve output cycling, board issues, random alarms etc. We have the boiler lit finally and they are going to propose an upgrade with a new backplane and new boards. The boiler is having a schedule outage later this year and we will look into the upgrade if that is the route they go. Thank you all for the tips and take care of yourselves.
Hi

Thank you for this feedback!
 
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