PiControl's PITOPS software is the most modern, best software for tuning PID control loops. PITOPS has advanced PID tuning functionality not available in any other PID tuning software from any other vendor. Below are the PID control loop tuning functionalities that make PITOPS the #1 PID tuning software in the world.
PITOPS PID tuning and close-loop dynamic model specifications are world-class, modern and sophisticated:
Vendor to quote on PID tuning software for use in control rooms for improving tuning of control loops. Software must be capable of working with any of the DCS or PLC vendors worldwide including but not limited to Mitsubishi, Allen Bradley Rockwell, Siemens PCS7 and other PLCs, GE, ABB, Honeywell, Emerson, Foxboro, Yokogawa and other less known vendors. Various plants are equipped with different PLCs, DCSs and SCADA systems and the tuning software must be easy to set to tune any PID from any vendor. PID equation to be tuned may be in ideal, interactive, parallel, series, integral only, proportional and derivative only and other different formats. PID equations format may be using error or PV on the proportional action and/or derivative action. Both positional and velocity forms must be supported.
The tuning software must be capable of identifying open-loop transfer functions with complete closed-loop or open-loop data. Data may not be available with the PIDs in manual or auto mode. The software must be capable of working with PIDs in not only auto but also cascade modes and must be able to identify open-loop transfer function models. Step testing may not be possible and the capability to use past historical data from some data historian with only cascade modes, setpoint ramping must be possible. The software must be able to work on multivariable identification problems - not just multiple cascade PID loops chained BUT also with multiple inputs. Example, hot oil, steam flow and electric heat may be three manipulated variables related to a controlled variable - temperature.
The software must be capable of analyzing multivariable inputs - hot oil, steam and electric heat and then identify three independent open-loop transfer functions (hot oil to temperature, steam to temperature and electric heat to temperature) even without step tests in the data. All calculations must be done only in the time domain - where time in milliseconds, minutes and seconds will be time units. Software must not use Laplace domain, frequency domain and discrete/Z domain. The need to convert to and from any domain other than time domain will not be acceptable. If there are unmeasured disturbances in the process, the software must be able to clearly isolate and display the unmeasured disturbance, this trend must be shown on the plots and then also must be capable of being saved in Excel format. Unmeasured disturbances will include random noise, drifts and unknow disturbances. For tuning optimization, the following PID tuning criteria must be available - IMC, Ziegler Nichols Open and Closed Loop, Cohen Coon, Lambda Tuning, IAE - integrated absolute error, ISE - integrated square error, ITAE - integrated time absolute error and the Reduced Overshoot criteria. PID tuning optimization must be possible amidst random PV signal noise, control valve stiction, ramp disturbances, pulse disturbances, sinusoidal disturbances, vector file signal disturbances.
The tuning criteria should allow for explicit rate of change in the control valve movement. The tuning algorithm must be capable of being told to not allow control valve movement or the slave PID setpoint movement by some maximum rate of change limit. The software must allow tuning for PI only or all three PID parameters. The model identification algorithm must be able to identify control valve stiction or deadband with both closed-loop data without step tests or open-loop data. The PID tuning algorithm must be capable of optimizing tuning for bad control valves that have stiction or deadband. For tuning, the user should be able to specify the control valve stiction or deadband identified by the dynamics identification module and then use it for the optimal tuning calculations.
Reports on tuning calculations and transfer function models and plots must be printable directly from the software user interface to PDF or printer. With many new personnel entering the control room, the software must have just 1 or 2 GUI screens for ease of use. User manual must be concise and under 75 pages maximum. Installation should be fast and easy with minimal support from vendor. Installation time should be only a few minutes and the time needed to start using the software needs to be under an hour.
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