Actuators, Regulators & Other Final Control - Recent Threads

FIELDVUE DVC6200 to FEEDBACK HART Conversion

Victor Blanco — Wed, 07 May 2025 16:12:44 GMT

We have ninety-two (92) FISHER control valves with FIELDVUE DVC6200 positioners in stock for a project that will be reactivated soon. Due to modifications to the control strategy, it is now necessary to obtain the feedback signal from each positioner, but due to control system limitations, it is not possible to add the hardware for 92 AIs. The option we are exploring is to add the necessary hardware to each positioner and implement a HART serial system that collects all the status information and delivers it to the control system. If necessary and advisable, the control signals (AOs) could be included in this HART serial system, but for now, we are only interested in the AI feedback signals. We formally request EMERSON's support and guidance to obtain the best solution for this requirement!

DCMLink and TEC2

Hussein Abdulwahid — Tue, 21 Jan 2025 12:47:09 GMT

Hello

We have upgrade Tec2000 actuators to Tec2 , as in the upgrade manual its written to use DCMlink to access Tec2 setting, back and change them.

However, when we tried to connect to Tec2 with RS485 and DCMlink via pin 36 and 38 , there is no response from the Tec2 CCM card ( I assume it's the one responsible regarding the modbus communication ).

It is fully functional when it comes to open and close the valve and can chang the setting from the LDM, but I could find the TEC2 with the DCMLink (always nothing found)

So, I would be very grateful if one of you can guide me to make it work and establish a connection between TEC2 and DCMLink

Kind Regards

Control valve discharge flow exceeds requirements which makes the valve to oscillate often.

E15 — Fri, 20 Dec 2024 14:31:42 GMT

Hello experts and Andre Dicaire

We have a Fisher control valve calibrated for a 0-100% span corresponding to 4-20mA. However, with less than 2% valve opening, the discharge flow exceeds the downstream requirements, causing the valve to repeatedly open and close, resulting in oscillations.

The valve is a 2-inch model, recently calibrated, and the operating range of the process line should be 0-8%. I dont have much information at this time?

To address this, would adjusting the valve span to map 0-8% to 4-20mA help stabilize the system? Alternatively, should we consider replacing the valve with a 1-inch valve or installing a back-pressure regulating valve helps?

Expert in the house, which option would be most effective and reasons?

Steam flow control valve

john — Thu, 06 Oct 2022 14:44:15 GMT

I have a flow control valve for steam, where the trend across 4 months period shows that the valve opening is different, for the same PV. Meaning the valve opening is going from 64% up to 90 something % for a steam flow of almost constant around 70t/hrs. Any reason why such variation in the control valve ? If there is a problem , any way to troubleshoot this and what parameters to look at ?

Thank you

Your thoughts please

Thank you

SIS Requirements for valve assemblies

Jake Parsons — Fri, 19 Aug 2022 19:48:21 GMT

How does emerson define SIS requirements for valves? From what I have seen the general consensus is that the "final element" is rated to IEC 61508 standard. Where the "final element" notation stops is where I am having the issue. We have pneumatic shut off valves going back to the SIS system. The solenoid valve that controls air to the actuator has an IEC 61508 certification but I cannot find the same certification on any valve or actuator. Is there a comparable ISO standard that the mechanical elements follow or am I not looking hard enough for IEC 61508 valves and actuators?

Valvelink Database Export/Import

Shaiq Bashir — Mon, 18 Apr 2022 19:42:32 GMT

I would like to know the following:

1) Is it possible to export the database from Valvelink SOLO version and import it in AMS Device Manager with Valvelink SNAP ON (with different system ID)?

2) Is it possible to export the database from AMS Device Manager with Valvelink SNAPON and import it on the system with different system ID?

Regards

Control valve flashing

john — Tue, 05 Apr 2022 21:11:28 GMT

Hello

Question please,

Can I operate a control valve at low flow rate/valve opening for a short time (during startup for example ) even if I know at this point, flashing or cavitation may occur? I will be operating the valve at a value less than the minimum flow rate the valve is sized based on.

Also, does the valve datasheet show when flashing occurs or I have to do calculation again for that purpose ..

Your inputs please from experience

Thank you..

DVC6200 and DVC6200SIS with or without SOV

Cristobal Ruiz — Wed, 12 Jan 2022 04:49:43 GMT

Greetings,

We are looking for ways to optimize our design and reduce the total cost of installation. During our design review I remember that it is possible to use the DVC itself to operate an on/off valve without a SOV.

How often do you see the DVC6200/DVC6200SIS used as "standalone" without an SOV? I understand that the SOV can be use as a 1oo2 type of arrangement but what if I don't need that voting?

For valves that require a fast open/close, is a quick exhaust necessary if I am using single-acting spring return actuators if I use the DVC without a SOV?

Regards.

Triggered Profile Memory Buffer

Shaiq Bashir — Fri, 09 Jul 2021 04:53:48 GMT

Dear Emerson Experts

Reference Positioner: DVC6200 PD

If I enable triggered profile, how much trigger events its buffer can hold?

Suppose, there is a chance that there will be two to three different trigger events in 24 hours at different times. Will it hold data for all of them or only the last one? Does the last trigger event overwrites the previous one or is it necessary to clear the buffer first in order to let the next trigger event to be recorded?

Regards

hydraulic actuator fail safe action as fail last

john — Sun, 04 Jul 2021 02:06:09 GMT

we have a hydraulic actuator installed at our site which we want to modify to have the fail action position as fail last, for both power failure and hydraulic failure. I see there are two options for power failure case, option one is to keep the actuator full of hydraulic (two hydraulic operated pilot valves for open and close as normally open, meaning hydraulic keeps flowing to actuator during power failure) and the other option is to cut the hydraulic supply to the actuator during power failure, through the closing of pilot valves. My question is , is there an advantage of one option over an another and which one I have to go for ?

Thank you for your comments

Velocity Gain

Garrett Kopcso — Mon, 21 Jun 2021 15:32:43 GMT

The definitions provided in the manual are absolutely useless (Below I copied them out the manual)

Can you please post the definitions of the items below?

Proportional Gain—the proportional gain for the travel control tuning set. Changing this parameter will also change the tuning set to Expert.

Velocity Gain—the velocity gain for the travel control tuning set. Changing this parameter will also change the tuning set to Expert.

MLFB Gain—the minor loop feedback gain for the travel control tuning set. Changing this parameter will also change the tuning set to Expert.

Integral Enable—Yes or No. Enable the integral setting to improve static performance by correcting for error that exists between the travel target and actual travel. Travel Integral Control is enabled by default.

Integral Gain—Travel Integral Gain is the ratio of the change in output to the change in input, based on the control action in which the output is proportional to the time integral of the input.

Lo Limit/Cutoff Point Change in DVC6200 Positioners

Shaiq Bashir — Tue, 01 Jun 2021 20:21:43 GMT

Dear Emerson Support

We are using the following DVC6200 series positioner:

FW Rev = 6

SNO# F001539833

HW Rev=2

HART Rev=5

We configured Lo Limit/Cutoff point in our DVC6200 positioners at 10%. Now the positioner is in service and we want to change it to 5%. But the Valvelink is not allowing us to do so. Is this feature only editable when the valve is out of service?

If it requires the valve to be out of service, then when we will change the valve mode to be out of service, will the valve hold its position or will move to some extreme position?

Is there any DVC6200 document which clearly informs which features can be edited online and which need valve to be out of service?

Thanks in advance.

Regards

DVC 6200 power failure action

john — Wed, 21 Apr 2021 08:43:58 GMT

what is the action of DVC 6200 for double acting actuator during DVC power loss in terms of output to actuator. To convert from valve Fail close to fail open action or vise versa, is change in DVC configuration required?

Thank you

Converting air failure position for valves

john — Sun, 18 Apr 2021 13:19:56 GMT

Is it possible to convert fail close control valve to fail open control valve. Valve already installed at site.

Your comments please from experience.

DVC 6200 Ovation/Valvelink

Bradley G — Mon, 25 Jan 2021 14:05:41 GMT

Hello, I am having an issue with Ovation DCS that is utilizing hart communication utilizing AMS to DVC6200 through a multiplexer, and a laptop utilizing Valvelink software connected to the ethernet port on the multiplexer is not allowing the laptop to communicate when ovation is connected. I believe this is due to the Hart signal coming from ovation and cannot communicate over the same line, or is the issue master/secondary master?

Thanks

DVC 6030 performance

Ismail Ramadan — Mon, 25 Jan 2021 12:39:56 GMT

We have DVC6030 positioner installed on Bettis rotary valve , after calibration valve is responding good in closing with difference max. 1-2%

bun doesn't opening good ,difference exceeds 10-15 %

positioner was calibrated several times with calibration complete message , but same behavior .

please Advise

valve position transmitter Vs DVC inbuilt position feedback

john — Sun, 24 Jan 2021 08:10:26 GMT

Is there a difference between using independent position transmitter for valve position feedback and using DVC inbuilt position feedback in terms of giving no error between command and feedback even though small errors? Do independent position transmitters create errors and need to be calibrated frequently ? Appreciate your comments from experience please.

Thank you

DVC6000SIS

Diaa Ghonaim — Tue, 17 Nov 2020 07:07:55 GMT

Hello

We faced a problem with one of our rotary SIS valve when a poisoner toke the valve toward faille plosion for 3 min then opened again by itself without a change in command signal. When maintenance team attend the valve they notice air is bleeding in pulses manner. There was no alert triggered beside travel deviation alarm.

due to the criticality of the valve The poisoner then replaced with 6200sis.

The poisoner then put in a bench on a test valve and same scenario happen air start bleeding in pulses manner no alert triggered, after I/P and Relay replaced the bleeding stopped.

our PM include a visual check for the valve and poisoner components. but the PM intervals varies from valve to valve it could be as short as 1 month to 6 years.

Our question how to prevent that from reoccurrence to the rest of the valves?

Thank you in advance.

DVC6200 COPY CONFIGURATION FROM DIFFERENT HARDWARE REVISIONS

A.A — Sat, 07 Nov 2020 09:30:53 GMT

Is it possible to copy the configuration of DVC6200 Hardware one (HD1) to DVC6200 Hardware two (HD2) through any of the following tools like VALVELINK SNAP-ON or VALVELINK SOLO ?

or I have to enter the configuration manually.

Oversizing - Improving Regulator Turndown using Restricted Trim

Nathan Wilhelm — Wed, 09 Sep 2020 16:39:03 GMT

Reduced orifice sizes and characterized cages are inexpensive ways of improving a regulator’s turndown capability. These restricted trims help low flow performance by increasing the travel at low flows, moving the valve plug further off the orifice.

Restricted trim types that improve low flow performance:

Changing to a smaller orifice (ex: numerous self-ops and a few pilot-ops)
- On products without alternate orifices, use a smaller body size

Characterized trim (ex: 310A turbine start-up, 1098 linear and whisper cage, 133 restricted collar)

An additional attribute of these restricted trims is that in many cases the wide-open flow is also lowered which can reduce the size of a relief valve being used for overpressure protection. Confusion arises on some products with trims designed solely for reducing the wide-open flow with users expecting them to improve low flow performance. Because these Relief Size-reduction Trims don’t affect the flow area size when the valve plug is at low travel, they do not improve turndown.

Relief Size-reduction Trim examples:

Travel stops (1098)
Upstream orifice plates (EZR and EZH)

Because Relief Size-reduction Trims do not improve a regulator's turndown, use the 100% capacity when using turndown rules-of-thumb, not the reduced capacity.

% of opening of Regulator

amitzala — Tue, 08 Sep 2020 02:02:41 GMT

I want to understand that what would be the minimum % of opening of regulator is recommended and which International guideline need to follow for % of opening of regulator.

Baumann 84000 - Typical Maintenance Issues - Valve Signature

Gerard Nagle — Fri, 04 Sep 2020 11:50:49 GMT

Hi there,

Questions about the Baumann 84000 Sanitary Control Valve.

What are the typical maintenance issues seen with this control valve. As it has a Diaphragm, Closure Member, this must have a limit on number of cycles or general loss of function over time. Is there guidelines on this?

For the tell tale port, is it possible to put a sensor onto the valve there, such as say pressure etc for a remote warning?

Also, what will the valve signature for this type of valve be in valvelink? will it be much, if any different from a typical non diaphragm?

Thanks you,

Ger

Oversizing - 7 Incorrect Regulator Sizing Practices

Nathan Wilhelm — Mon, 03 Aug 2020 21:24:23 GMT

Oversizing pressure regulators creates premature failure, mechanical noise, and performance issues. Always choose the smallest product/orifice/body size that meets the maximum flow requirements at the minimum inlet pressure condition.

The top reasons for oversized regulators:

1. Selecting a regulator based off future demand, ignoring current demand that is merely a fraction.

2. Reasoning: more is always better, right?

3. Using the 30% monitor reduction sizing practice instead of proper monitor sizing

4. Choosing the regulator size based off the piping size instead of sizing off process conditions

5. Expecting too much turndown out of a single run of regulators instead of using parallel runs

6. Focusing more on outlet pipe velocity than proper regulator sizing. (Tip: Correctly size the regulator, then swage up the outlet piping to lower velocity)

7. Not trusting published flow values. Emerson stands by the published flow values because we’ve established them through extensive testing.

Upgrading the software level of DVC6200 from HC to AD

jeff richards — Tue, 28 Jul 2020 22:00:07 GMT

We have received a USB pen drive with upgrade license for some of our DVC6200 HC positioners.

As I understand it, the path to upgrading the license is via valvelink, so I have the following issue.

We only have valvelink on a Trex communicator (with micro USB connection) and a vendor laptop with valvelink solo express.

We are in a remote location and dont have a female USB to male micro USB connector to connect the pen drive to the Trex. It will take some time to source due to our location.

An option is to use a vendors laptop who has valve link solo express installed on an older laptop that is still running XP for legacy software issues, but I am unclear if the unused licenses remain on the pen drive or if they transfer to the laptop (which will leave the installation in the next week) once we start valve-link and start applying the license upgrades.

If you can advise as to the procedure for upgrading the DVC 6200s in our situation, it would be appreciated.

Regards

Jeff Richards

Oversizing – Pressure Regulator Turndown

Nathan Wilhelm — Tue, 21 Jul 2020 14:36:08 GMT

Pressure regulator turndown (i.e. rangeability or minimum flow) values are a common inquiry from customers who are sizing and selecting a regulator. It is a question that I’ve always dreaded answering. Why? Because the regulator’s capability is only part of the equation… process conditions and installation also impact stability and their impact is difficult to predict.

Oversizing (i.e. exceeding the regulator’s turndown) is the most common product selection issue. When a regulator is oversized, the valve plug is forced to operate very close to the orifice. At this low travel, the forces from the fluid flowing past the valve plug battles the regulator diaphragm trying to position the valve plug, causing the regulator to cycle: open, closed, open, closed… This high frequency cycling, known as instability, causes wear on the moving parts which can lead to component failure and loss of pressure control. This cycling can also produce significant noise and inaccurate pressure regulation.

Think of the turndown of a specific regulator type as a bell curve distribution. Construction options such as body size, orifice size, spring selections create variability. Add to that installation variability and you have a distribution of outcomes. Some variables combine to have excellent turndown and others combine to have poor turndown.

Due to this variability and the complex multi-factors, the best advice for turndown typically comes in the form of rules of thumb, handed down like an old family recipe from one generation to the next. Often, these rules of thumb are conservative but provide guidelines for when additional consideration is needed. When the calculated turndown is approaching the rule-of-thumb threshold:

Evaluate how realistic the maximum inlet and minimum flowrate values are and the likelihood that they will simultaneously occur.
Consider how long the regulator might be expected to operate at this extreme turndown. Some applications exist where the extreme turndown requirement is real but brief and rare.
Consider using parallel runs