Non Programmable PID Controller
Non Programmable PID Controller
(OP)
I am looking for any information or datasheets about non programmable PID controllers, for use within nuclear safety systems.
Can anyone recommend any manufacturers/suppliers?
Can anyone recommend any manufacturers/suppliers?





RE: Non Programmable PID Controller
RE: Non Programmable PID Controller
What do you mean by non-progarmmable PID controller? Can you clarify and be a bit more precise. Most safety systems usually do not use a lot of PID controllers. Controller control, and is usually found in the DCS or control system.
JL,
A pneumatic controller, like the 43AP is still "programmable", you just open the lid, and move the knobs. You may make an arguement that is is not remotely progarmmable, but it is programmable none the less in my opinion.
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RE: Non Programmable PID Controller
RE: Non Programmable PID Controller
If you tell us the application you will save a lot of time and get much better information.
yours
RE: Non Programmable PID Controller
The application of the PID is for the control of pressure in a nuclear system. The controller must be SIL 2 compliant and needs to have an analogue input and digital outputs. When I specified non programmable, I was referring to the controller not being adjustable.
RE: Non Programmable PID Controller
Any DCS PID control function block may be "locked" out via password protection from the operator, engineer, etc - anyone who doesn't have the password.
I would suggest you contact your safety system vendor and see what they offer. I has been at least 4 years since I last programmed a safety system (Honeywell FSC), so things may have changed since.
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RE: Non Programmable PID Controller
http://www.flaminsystems.com/page/page/2424482.htm
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RE: Non Programmable PID Controller
RE: Non Programmable PID Controller
.... but tuning the PID gains to respond to the system pressure based on your performance objective is what defines them. The dynamics of each process is different so controller gains will be different. Also, you will have different controller gains for the same process if you have different performance objectives.
I do not think that you can get one out of the box and simply plug-and-play. Besides, wouldn't you want to re-tune this thing down the road when some other component in your reactor start to give?
Now, if you want self-tuning controllers, that is a different story.
Fulfilling the requirement for an anolog and numerous digital inputs is easy.
RE: Non Programmable PID Controller
PID is for control, and usually in the "control system".
I think andy345 you may want to revisit what you have set up in your control system vs. safety system.
The safety system is a separate system. I have not seen PID control function in a safety system.
If anyone else has, would they like to share?
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Non Programmable PID Controller
RE: Non Programmable PID Controller
Is this a case where a "safety system equipment" is used in a "control system" application - the burner managment?
BMS typically have their owne "control system". An external safety systems sends an output to the BMS to "shut it down".
This is more typical of what I have seen.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Non Programmable PID Controller
Autonomous control systems might have features that match the safety system design but seperate than a plant shutdown system. These equipment systems likely include PID control. This is true of other specialized equipment control systems such as gas turbine driven compressors or generators. A plant could have a heater or compressor control system that controls the all equipment stuff including the process and fuel inlet shutdown valves. However, (my perfect world) plant would still have process and fuel shutdown valves outside the heater controls. A plant ESD hazard such as a fire would trip the safety system valves regardless of the equipment control system logic. Depending upon the process hazard analysis and SIL study results I might or might not require the process safety shutdown system to include separate instruments within the "equipment" boundry limits. If it is a package heater using waste heat to preheat a hydrocarbon stream I would expect more safety system instruments within the equipment package than if it were a boiler for an institutional building.
RE: Non Programmable PID Controller
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Non Programmable PID Controller
"nuclear safety systems". This is all we had to go by.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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RE: Non Programmable PID Controller
Are you sure that the controller needs to be SIL 2? An easier way would be to install a separate pressure SIF independent of the PID controller and implement that within your logic solver.
I agree with Ashereng... any PID is somewhat programmable and even changing the tuning parameters can severely change the operation of the loop and even disable it. To answer Ashereng's question... I have never used a PID loop in a safety system. I do believe that HIMA includes it in their system (H41 and H51) and perhaps Triconex. Others could have the ability but they would not be considered safety rated as part of their TUV certificate. I also think that Yokagowa Centum DCS is TUV certified to SIL 1.
In all of my experience with safety, I have only come across one SIF that was classified as continuous but it was still an on/off valve (the reason was that the operating pressure was very close to the trip set point and trips were expected frequently... don't ask, not my design).
A little late, but hope it helps.
sdl
RE: Non Programmable PID Controller
Thanks for your response.
My point was that I too have NEVER seen a PID control loop in a safety system.
If it is controlling something, it is part of the control system.
"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
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