The 375 Field Communicator is designed to work both as a “Bench Tool” and as a “Field Tool.”

• As a Bench Tool, the 375 Field Communicator would typically be connected to one or more FOUNDATION fieldbus devices on the bench with no other host system connected to the segment.
• As a Field Tool, the 375 Field Communicator would be connected to a live FOUNDATION fieldbus segment in the field that is controlled by a Host Control System.

Normally (but not always) this Host Control System acts as the Link Active Scheduler (LAS) for the segment. When the 375 Field Communicator detects that there is a LAS on the segment, it joins the segment as a “guest”. For most operations, the Host Control System and the 375 Field Communicator should be able to co-exist on the FOUNDATION  fieldbus segment with no problems. Other operations, such as changing the node address of a fieldbus segment, require careful coordination between the Host Control System and the 375 Field Communicator.

Some operations with the 375 Field Communicator are simply not advised if there is a Host Control System on the segment. Some operations (such as changing a device address, changing a device tag, or commissioning / decommissioning a device) with either the 375 Field Communicator or the Host are simply not advised if both a 375 Field Communicator and a Host Control System are on a segment at the same time.

In light of all this, a set of Host System Interoperability Tests has been run with the 375 Field Communicator. Initially, this complete set of tests has been run only with the DeltaV™ digital automation system from Emerson Process Management. These tests will be run with other Host Control Systems in the future and the results placed here.

Results of 375 Field Communicator Interoperability Testing with DeltaV

The results of testing the 375 Field Communicator with the DeltaV™ digital automation system are given in table form. Each row in this table indicates a specific FOUNDATION fieldbus feature. For each feature, there are two sets of three columns each. The first set of three columns refers to support for this feature on the 375 Field Communicator when it is used on the bench (i.e. without a Host Control System connected). The second set of three columns refer to support for this feature on the 375 Field Communicator when it is connected to a segment with a DeltaV connected. An “X” in each of the sub columns indicates the following:

• S - The feature is supported on the 375 Field Communicator.
• NSB – The feature is not supported on the 375 Field Communicator and is, in fact, blocked from being performed on the unit.
• NSNB – The feature is not supported on the 375 Field Communicator, but no specific means have been taken to block the use of this feature. Users attempting this feature do so at their own risk.

375 Field Communicator Interoperability Testing with Other Host Systems

The testing described above is in the process of being performed with other Host Systems. The results, when available, will be placed here. Until then, care should be taken when connecting the 375 Field Communicator to a FOUNDATION fieldbus segment controlled by another Host Control System.