Auma Motorized Valve Setting

Here's an idea. Auma's technical helpline.

I think, the only thing we can do in case of MOVs is :

to minimize the Mechanical Torque at the Erection stages, Coz that is the most problematic thing hence producing probs in later stages .

Secondly, while commissioning the MOVs ,we do a Setting of Limit Switches and Torque Switches ,for Fully Open and Fully Close Positions . If that is not done properly it can never fully close.(I think you must have taken care of these yourself.)

If we talk about Travel f/b or Commands to open and Close or Positioning ,that you have to check out with PLC .

Apart from these Contact Auma People .By d way what size and type of valve is this .

thanks for the response. the size of our pipe is 4 inches and this MOV is installed for our start up vent on our boiler. we have no problem on our DCS signal. it's the valve that is not responding to 8mA or 25% opening.

where could i get their free helpline?

What do you mean "Free Helpline"? Just call the company and ask for an applications engineer.

Did you even do an internet search?

http://www.auma.com/cms/auma/en/

Come now guest - posting the same silly picture twice is no more help than posting it once. Now he has asked you directly for help with the telephone number that you insist he use there is no response from you. Truly, you are a helpful poster. Knowledgeable? - we do not know, you have contributed nothing to the discussion.

Quite the contrary he has contributed all that is needed. He even did it twice because he is dealing with a "novice" to be kind.

This is just a guess, but the valve seems sticky in the range where it is nearly closed. Maybe something caught in it? If it is a butterfly valve, some stickiness in that range would not be surprising; maybe a ball valve would be smoother.

Another thing I wonder: Is there a clutch in the gearmotor section that could be tightened without overloading the gearmotor?

Did this valve and actuator combination ever work properly?
For how long?
When did it start to misfunction?
What were the 3 most recent work orders on or about the valve/actuator assembly prior to the first misfunction?

Are the end-of-travel limit switches adjustable ?
Has the cover over the end-of-travel limit switches been removed recently?

Does the valve have a position indicator?
What leads you to believe that the position indicator indicates properly?

What happens when the actuator gets a 4mA signal?
What happens when the actuator gets a 6mA signal?
What happens when the actuator gets an 8mA signal?
What happens when the actuator gets an 10mA signal?

At what drive signal level does the valve respond properly? 10mA? 12mA?

What is the evidence of 'having a hard time'? Do fuses blow? Does the motor overheat? Does a clutch slip?

What is the travel time, end-to-end/stop-to-stop?

The medium in the pipe is _________ ?

sir i think i can relate to what you have post. when i check the valve at my yokogawa calibrator. i did a fine tune at 4mA at 0% and 20mA at 100%. the valve respond ok. but when tested on DCS, the actual output doesnt coincide. the DCS output for supposed to be 4mA=0% is 1.2mA thus when tuning on my calibrator at 1.2mA, the valve display at fault.

Does that mean that the actuator valve responds properly over the entire range, 4mA to 20mA when you use a current source calibrator?

The DCS output for 0% = 1.2mA? not 4.0mA?

What load are you testing the DCS output with? A resistor? a calibrator?

If it's a reasonable load (< 500 ohms) then your problem is NOT the valve/acutuator!

The problem is the current output or power supply for the current output from the DCS.

Yes you need to check the DCS output, May be try with a different output channel

first try the actuator alone without the valve and check if it is operating

atleast you know where the problem is with the valve or actuator

Having resolved that you can work on the problem area ,

thanks for all the points you've shared with me. i'll refer the dcs output to yokogawa because it is still their obligation. thanks a lot.

Check their website, you will get contact numbers and be able to download the manuals, including the troubleshooting guide.

Typically you need to ensure that the travel limits and torque limits are properly set and that the valve is moving freely with the handwheel. Does the valve have local push-buttons or switches for opening and closing? Do these work properly? i.e. will the valve start opening as soon as the open push button is activated and stop when is is deactivated? Does it stop at the end positions when the local push-buttons are used? If these things are fine then you may have a problem with the one of the interface/control boards.

I have never encountered one of these valves where calibration or adjustment of potentiometer was required, they work pretty reliably unless there is some component failure or some other external circumstances which may have contributed to the failure.

Good luck.