Please ask an expert for help with a problem regarding Siemens positioners
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I would like to ask some questions regarding Siemens positioners: 1. Is the direction of the signal provided by the DCS consistent with the manual +/– signals on site? 2. Is the setting for the pulley related to its upper limit range? What does it mean when the value goes back to 0 or becomes negative after reaching 0-100? I would be very grateful if experts could provide some guidance
I suggest you take a look at its manual; the URL is its download link: https://support.industry.siemens.com/cs/attachments/109763954/A5E35438965-ADzh_PS2HART_OI_zh-CHS.pdf?download=true
Contact Siemens after-sales as soon as possible. 400-616-2020 website ； https://new.siemens.com/cn/zh/company/about/hotline.html
First, power it on directly and check the actual output of the locator as well as its displayed output by manually triggering a signal through the DCS or PLC. If it matches the value from the DCS, then no further action is needed； If there is a discrepancy (usually the opposite, such as the DCS outputting 25% while the on-site output and display show 75%), then go to the locator menu on site, find the setting for “7.SDIR” – change it from Fall to Rise – and also change the setting for “38.YDIR”, which relates to the direction of the displayed and feedback values of the controlled variable, from Fall to Rise ；
The main issue is that it hasn’t been adjusted properly. 1. There are settings for positive and negative effects in the parameters, and these must match the actual situation. 2. Follow the method outlined in the manual to make the adjustments again
1. Is the direction of the signal provided by the DCS consistent with that of the manual +/– signals on site? Haiyou on the 4th floor has already answered this. 2. Is the upper limit range what is being adjusted for the pulley? Or how should we understand the function of this pulley? Why does the value go back to 0 or become negative after reaching 0-100? This pulley is essentially a variable resistor, only it operates in a cyclic manner – that is, after reaching the maximum resistance value, it decreases and then increases again, but the resistance range remains constant. This pulley is mainly used during debugging, such as setting the valve position resistances to 0% and 100% after initialization.