Logix5000 Controllers General Instructions - SLAC Confluence

Special Instructions (FBC, DDT, DTR, PID) 503Mnemonic: Data Type Description.DATA REAL[17] The .DATA member stores:Element: Description.DATA[0] integral accumulation.DATA[1] derivative smoothing temporary value.DATA[2] previous .PV value.DATA[3] previous .ERR value.DATA[4] previous valid .SP value.DATA[5] percent scaling constant.DATA[6] .PV scaling constant.DATA[7] derivative scaling constant.DATA[8] previous .KP value.DATA[9] previous .KI value.DATA[10] previous .KD value.DATA[11] dependent gain .KP.DATA[12] dependent gain .KI.DATA[13] dependent gain .KD.DATA[14] previous .CV value.DATA[15] .CV descaling constant.DATA[16] tieback descaling constant.EN BOOL enabled.CT BOOL cascade type (0=slave; 1=master).CL BOOL cascade loop (0=no; 1=yes).PVT BOOL process variable tracking (0=no; 1=yes).DOE BOOL derivative of (0=PV; 1=error).SWM BOOL software manual mode (0=no-auto; 1=yes- sw manual).CA BOOL control action (0 means E=SP-PV; 1 means E=PV-SP).MO BOOL station mode (0=automatic; 1=manual).PE BOOL PID equation (0=independent; 1=dependent).NDF BOOL no derivative smoothing(0=derivative smoothing filter enabled; 1=derivative smoothing filter disabled).NOBC BOOL no bias back calculation(0=bias back calculation enabled; 1=bias back calculation disabled).NOZC BOOL no zero crossing deadband(0=deadband is zero crossing; 1=deadband is not zero crossing).INI BOOL PID initialized (0=no; 1=yes).SPOR BOOL setpoint out of range (0=no; 1=yes).OLL BOOL CV is below minimum output limit (0=no; 1=yes).OLH BOOL CV is above maximum output limit (0=no; 1=yes)Publication 1756-RM003I-EN-P - January 2007