Solver Setting  Integration
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Navigation: User Guide ➔ Menu Commands ➔ View ➔ Solver Settings ➔ Integration
This page is for Build 138 or earlier. For Build 139 or later, please see Solver Setting  Method.
Tag (Long/Short) 
Input / Calc 
Description 
Dynamic Solver Settings  
RealTime.On  Tickbox  SysCAD will solve the model at a speed relative to the time on your PC. If the RealTimeMultiplier is set to 1 (100%), then it will take 1 second of running time to simulate 1 second of real time. 
RealTime.Multiplier  Input  Multiplier of time when using the RealTime option. If the RealTimeMulitplier is set to 2 (200%), then it will take 1 second of running time to simulate 2 seconds of real time. 
StepSize  Input  The size (time) of each step. A higher value results in a faster relative speed, but generally a less accurate solution. The maximum step size that can be used is dependent on the dynamics of process (relative flow rates, volumes of units, timing of events, etc). A single step can have multiple iterations to solve the flowsheet and associated controls, similar to solving a steady state project. The maximum number of iterations per step is set on the Tears tab . 
StepsPerUpdate  Input  Determines how many steps will be solved before the number displays in trend windows and so on are updated (or stored in historian). Generally the number of Steps per Update is set to 1 so that the number displays are updated at the end of each step. 
Integration  
Method  Input  The method used for the dynamic simulation can be changed here.

TimeInc.Control  Input/Display  Only the Fixed option can be selected. 
TimeInc.Max  Input/Display  Maximum step size. 
TimeInc.Min  Input/Display  Minimum step size. 
Mag.RelTol  Input/Display  Relative tolerance. Can only be changed with the RungeKutta 4 method. 
Mag.AbsTol  Input/Display  Absolute tolerance. Can only be changed with the RungeKutta 4 method. 
IntSafety  Input  
DerivEstInc  Input  
SettleTime  Input  
GrowLimit  Input  
Grow  Input  
OKShrinkLimit  Input  
OKShrink  Input  
BADShrink  Input 