Plantstruxure Unity Opc Software Page 1-14 Unity Pro software

1/14 Functions (continued) Software Unity Pro software Small/Large/Extra Large Programmable process control Process control in machines Unity Pro contains CONT_CTL, a library of 36 function blocks used to create control loops for machine control. The requirements for closed loop control functions in machines are adequately met by Modicon M340, Modicon M580, Modicon Momentum, Premium and Quantum platforms thanks to the wealth of functions in the library and the flexibility with which function blocks can be linked together through programming. This solution therefore avoids the need for external controllers and simplifies the overall control architecture of the machine, as well as its design, roll-out and operation. The EFs or EFBs can be used in any of the Unity Pro languages (LD, ST, IL and FBD). FBD is particularly suitable for accessing control processing operations in Unity Pro through its wizard for entering and viewing parameters and function block variables. CONT_CTL library functions The library consists of six function families: b input data conditioning b controllers b mathematical functions b process value processing b output value processing b setpoint management Input data conditioning DTIME Pure time delay INTEGRATOR Integrator with limiting LAG_FILTER First order time lag LDLG Lead/lag function with smoothing LEAD Lead function with smoothing MFLOW Mass flow calculation based on the measurement of differential pressure or flow speed with pressure and temperature compensation QDTIME Dead time term SCALING Scaling TOTALIZER Integrator (typically of flow) until a limit (typically a volume) is reached, with automatic reset VEL_LIM Velocity limiter, with manipulated variable limiting Controllers PI_B Basic PI controller: PI algorithm with a mixed structure (series/parallel) PIDFF Complete PID controller: PID algorithm with a parallel or mixed structure (series/parallel) AUTOTUNE Automatic tuner setting for the PIDFF (complete PID) controller or the PI_B (simple PI) controller v Identification using Ziegler Nichols type method v Modeling based on first-order process v Building of control parameters with criterion for prioritizing either the reaction time to disturbance (dynamic) or the stability of the process IMC Model-based controller. The model is a first-order model with delay. This corrector is useful: v When there are serious delays compared with the main time constant of the process; this scenario cannot be satisfactorily resolved by standard PID process control. v For regulating a non-linear process IMC can handle any stable aperiodic process of any order. SAMPLETM Control of controller startup and sampling STEP2 Simple two-position controller STEP3 Three-position controller for temperature regulation Mathematical functions COMP_DB Comparison of two values, with dead zone and hysteresis K_SQRT Square root, with weighting and threshold, useful for linearization of flow measurements MULDIV_W Weighted multiplication/division of 3 numerical values SUM_W Weighted summing of 3 numerical values CONT_CTL, programmable process control integrated in Unity Pro AUTOTUNE PV SP RCPY START PREV PARA TR_I TR_S PV_O SP_O PARA_C TRI TRS INFO STATUS TT18_PV TT18_SP TC18_OUT TC18_START TC18_PREV TC_PARA TC18_PARA TC18_OUT 1 TC2_OUT TC18_OUT PV SP PARA TR_I TR_S PIDFF FF RCPY MAN_AUTO OUT OUTD MA_O INFO STATUT TC2_OUT MS TC18_OUT IN PARA TR_I TR_S FORC MA_FORC MAN_AUTO OUT OUTD MA_O STATUT Example: PID controller with MS manual control Selection guide: page 1/2 2 1 3 4 5 6 7 8 9 10 2 1 3 4 5 6 7 8 9 10

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