Meaning of DCS Symbols in Yokogawa VP System (II)

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MODE: Mode. SH: PV scale high limit – the upper limit of the measurement range. SL: PV scale low limit – the lower limit of the measurement range. PV: Presses variable – the actual measured value on-site. OUT_V: Output value – the value that is outputted. ALARM: Alarm signal. HH: High-high limit alarm set point – the set value for the high-high limit alarm. PH: High-limit alarm set point – the set value for the high-limit alarm. PL: Low-limit alarm set point – the set value for the low-limit alarm. LL: Low-low limit alarm set point – the set value for the low-low limit alarm. P01: Extended Parameters 01 – Extended parameter 01. P02: Extended Parameters 02 – Extended parameter 02. P03: Extended Parameters 03 – Extended parameter 03. P04: Extended Parameters 04 – Extended parameter 04. BSTS: Module status (this module does not have this function). MODE: Mode. SH: PV scale high limit – the upper limit of the measurement range. SL: PV scale low limit – the lower limit of the measurement range. PV: Presses variable – the actual measured value on-site. SV: Set point value – the desired value. MV: Manipulated output value – the value that is actually outputted. READBACK: Read back value – the value that is sent back after reading. MSH: MV Scale high limit – the upper limit of the MV scale. MSL: MV Scale low limit – the lower limit of the MV scale. OPHI: Output high-limit index – the index related to the output high limit. OPLI: Output low-limit index – the index related to the output low limit. ALARM: Alarm status. SVH: Set point high limit – the upper limit of the set point. SVL: Set point low limit – the lower limit of the set point. FST_VAL: Fault state value – the value indicating the fault condition. P01: Extended Parameters 01 – Extended parameter 01. P02: Extended Parameters 02 – Extended parameter 02. P03: Extended Parameters 03 – Extended parameter 03. P04: Extended Parameters 04 – Extended parameter 04. BSTS: Module status (this module does not have this function). Commonly used functions: 1. Modifying the measurement range. During production, the range of the originally designed instrument may not be sufficient for the requirements; in such cases, it is necessary to adjust the range to a suitable level based on the maximum range of the on-site measuring device. After the range of the field measurement instrument is modified, the range in the DCS matches that of the field instrument; otherwise, the values displayed by the DCS will be inaccurate. 2. When the process conditions change during operation or when the alarm values specified in the design do not meet the actual requirements, frequent alarms occur in the DCS. In such cases, it is necessary to modify alarm values such as HH, HI, LL, LI, and DL in TUN in order to meet the desired alarm settings. 3. Setting of output limits 1. Adjusting the PID parameters of the controller 1. Using the PRD function in complex control loops