LabVIEW DSC Module to FieldPoint Connectivity

You can connect to National Instruments FieldPoint modules in three different ways from the LabVIEW Datalogging and Supervisory Control (DSC) module:

• FieldPoint Industrial Automation (IAS) Server connection
• OPCFieldPoint connection through the built-in OPC Client
• Direct Logos connection (only available for FieldPoint Ethernet modules)

There are several things to consider when choosing which method that you use for communications between the LabVIEW DSC module and FieldPoint. Ultimately, the choice comes down to your specific needs.

• Communication Compatibility: Using the Logos networking option, you are unable to switch between FieldPoint Ethernet Network Modules and Serial Network Modules. Using both the OPC and FieldPoint IAS methods, it is fairly trivial to do so.

• Maintenance: FieldPoint network modules and the FieldPoint OPC Server have the ability to learn new I/O modules as they release (with very few exceptions that require firmware and/or FieldPoint Explorer upgrades); however, the FieldPoint IAS does not have this ability and can sometimes not support new modules for several months. Also, new versions of the LabVIEW DSC module require an updated version of the FieldPoint Explorer.

• Error Information: For different reasons such as loss of power to a FieldPoint bank, error messages may be returned. In addition, some modules support channel specific error messages (e.g. Open RTD on the FP-RTD-122 or Out of Range on the FP-AI-110).  This information will be displayed best by the FieldPoint IAS. The FieldPoint OPC Server converts most of the errors to "Bad Status". The Tag Status gives either - bad quality or out of range error. The Logos connection also converts most of the errors to Bad Status only.

• Configuration: Using the FieldPoint IAS and the FieldPoint OPC Server, you have the ability to read/write data to an I/O point and to change its attributes (e.g. filter setting); however, you cannot change the range of the I/O point (e.g. 0 - 5 Volts vs 0 - 10 Volts). Using the Logos networking option, you can change the range of an I/O point.

• Third Party Connectivity: Both IAS Server and Logos are proprietary communication protocols. If you want to expose the FieldPoint measurements to a third party software or plan to do so in the future, you should choose the OPC Server. OPC is an open industry standard.

• Dial-Up: Currently, none of these method supports dial-up connections. If you need that ability, you have to use Lookout Protocol Drivers and its native FieldPoint.CBX driver.

Generally speaking, we recommend the OPCFieldPoint. Use the Logos networking option if you need the ability to dynamically change the range of a channel. The only reason to use the Lookout Protocol Drivers is to have dial-up support. The IAS Server currently exists mostly for compatibility reasons with existing applications.

The following table summarizes the outlined issues:

	IAS Server	OPC Server	Logos	Notes
Network Module Types	Serial, Ethernet	Serial, Ethernet	Ethernet
Maintenance	Requires updates for new modules and new LabVIEW DSC module versions	Minimum	Minimum
Dial-up Support	No	No	N/A	Use Lookout Protocol Drivers
Error Information	Descriptive alarms and errors	General Bad Status alarm	General Bad Status alarm
On-the-fly Configuration	Change Attributes	Change Attributes	Change Attributes + Channel Ranges
Alarm Delay after Losing Communication	<5 sec (Ethernet)	< 5 sec (Ethernet)	10-15 sec (Ethernet)	Serial Modules Faster
Alarm Deactivation Delay after Reconnecting	10-20 sec (Ethernet)	10-20 sec (Ethernet)	10-20 sec (Ethernet)	Serial Modules Faster
Industry Standard	Proprietary	Yes	Proprietary

Related Links:
Using FieldPoint OPC Server with the LabVIEW DSC Module
Using FieldPoint Logos Server with the LabVIEW DSC Module

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