Compact FieldPoint Frequently Asked Questions (3 of 3)

National Instruments Compact FieldPoint is an easy-to-use, highly expandable industrial control and measurement system composed of rugged and dependable I/O modules and intelligent controllers. Many types of I/O modules are available, so you can connect a wide variety of sensors to the system. Compact FieldPoint I/O modules filter, calibrate, and scale raw sensor signals to engineering units. You can download your LabVIEW application to the embedded controller for reliable stand-alone operation. Compact FieldPoint network communication allows you to access I/O points nearby or miles away on the network using the same simple read/write software framework.

Compact FieldPoint Frequently Asked Questions (1 of 3)

Compact FieldPoint Frequently Asked Questions (2 of 3)

Can I Use Autotuning PID with Compact FieldPoint?

The PID Control Toolkit for LabVIEW includes autotuning PID capabilities that can execute an automatic testing process to determine the PID gains that will provide the best performance. This means you can tune your PID control system with minimal effort and without the need for detailed knowledge of PID tuning.

In LabVIEW, the PID Autotuning VI function includes an autotuning wizard that will guide you through the process. Note that you must obtain a minimum level of stable (non-oscillatory) control before you can begin the autotuning process. The PID Autotuning VI must be run on the host computer, and cannot run embedded. Once you obtain the optimum PID gains, you can replace the PID Autotuning VI with PID VI or PID Advanced VI, which are suitable for embedded execution. For more information about autotuning, consult the PID Control Toolkit User Manual

See Also:
Manuals: PID Control Toolset User Manual
Developer Zone: PID Control Category

Can I Perform Simulation with Compact FieldPoint?

The PID Control Toolkit for LabVIEW provides powerful simulation capabilities that you can run as easily on the host computer as on the embedded Compact FieldPoint controller. Simulation is an important aspect of the control system development process. While not required, simulation allows you to leverage your knowledge of the system to select an appropriate control scheme and evaluate its performance. Simulation can help you make design decisions, such as refining the parameters for a PID controller. If you are able to obtain a model for the system, you can use simulation to quickly try different control techniques, evaluate design trade-offs, gain insight into the system, evaluate the robustness of your control design, and predict how the system will behave under worst-case conditions.

Can I Access the Compact FieldPoint Serial Ports Directly from the Host Computer?

No, the Compact FieldPoint serial ports are accessible only through embedded LabVIEW applications. However, communicating data from the embedded serial ports to the host computer programmatically is easy. One way is to create a custom OPC tag using the Publish Data VI and then write the serial data to that tag. The cFP-2020 controller has three RS-232 serial ports and one RS-485 serial port. The cFP-2010 controller has two RS-232 serial ports, and the cFP-2000 Controller has one RS-232 serial port.

How Do I Perform Historical Datalogging with Compact FieldPoint?

Historical datalogging is easy with Compact FieldPoint and the LabVIEW Datalogging and Supervisory Control module. In LabVIEW, navigate to Tools>Datalogging & Supervisory Control>Configure Tags. Then select the tag names you would like to log into the historical measurement database. These tags can include both Compact FieldPoint channels and third-party devices such as programmable logic controllers (PLCs) and other industrial devices. Finally, navigate to Tools>Datalogging & Supervisory Control>Monitor Tags.

You can also use the Flash for logging applications. LabVIEW File I/O VIs can be used to write the data to the Flash. The data can then be retrieved from the host computer through FTP. For logging applications, NI recommends the FP-2015 or the cFP-2020 with a large external Flash.

See Also:
Products and Services: LabVIEW Datalogging and Supervisory Control Module
Developer Zone: Performing Embedded Data Logging with FieldPoint

Is Measurement Accuracy Important for Industrial Control Systems?

You can control a process only as accurately as you measure it. Analog control systems consist of three components: input, control algorithm, and output. The accuracy of all three components determines the overall quality of your control system. Compact FieldPoint I/O modules feature 12- or 16-bit resolution and ship with a NIST calibration certificate to guarantee measurement accuracy. Compact FieldPoint controllers use a floating-point processor with the ability to perform 128-bit math calculations in LabVIEW. With an easy-to-use read/write programming interface, and drop-down blocks for control functions from basic PID to advanced control algorithms, Compact FieldPoint and LabVIEW make developing embedded analog control systems easy.

Can I Add Compact FieldPoint to an Industrial Automation System that Contains PLCs?

Compact FieldPoint makes it easy to add powerful control, measurement, datalogging, and signal processing capabilities to systems containing PLCs. FieldPoint Explorer includes an OPC server that can work with any OPC client. The LabVIEW Datalogging and Supervisory Control Module can gather data from any OPC Server, including the FieldPoint OPC Server, the Lookout Protocol Drivers OPC Server, or any third-party OPC server. Lookout Protocol Drivers (Industrial Automation OPC Servers CD) includes drivers for more than 100 industrial device types, making it easy to create a hybrid system containing many different devices and communication protocols.

See Also:
Products and Services: LabVIEW Datalogging and Supervisory Contorl Module
Products and Services: Industrial Automation OPC Servers CD (Lookout Protocol Drivers)

Related Links:
Compact FieldPoint Frequenlty Asked Questions (1 of 3)
Compact FieldPoint Frequently Asked Questions (2 of 3)

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