Seeking help with ABB positioners
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For an ABB actuator used with a butterfly valve, the feedback value is always lower than the set value, which causes the DCS to indicate that the valve is in the open position. The same issue occurs even after recalibrating the settings. I would appreciate it if experts could help analyze what might be the cause of this problem.
Just re-adjust the locator on site
This post was last edited by SuiboZhuiliu_zXBNX on 2021-2-5 at 09:58. An error of just a few hundredths of a percent is still quite precise; if closing the valve is to be confirmed on-site, set the DCS to close when the value is below 0.5%
I’m not quite sure about the picture you sent – is the opening degree of the valves around 27% in both cases? Your valve inspection status is incorrect
For the one on the left, the given value is 27 while the feedback value is 26.7; it cannot reach 27, so it remains in the valve-open state as shown. The one on the right indicates that the valve opening process has been completed. The on-site locator shows the same opening value as that displayed on the DCS, which is 26.7. This causes the on-site locator to keep operating repeatedly
I don’t know where to set it; is it possible to set it?
Command 27%, response time 26.7% – very good. There’s no need to adjust the locator. Check the DCS settings to see the range of deviation values for commands and responses
In fact, the valve on your right has a greater deviation: command value is 27%, while the feedback value is 27.4%
Okay, I’ll see at that time. Thank you