SLS 1508 SIS Network domains

As SLS 1508 SIS applications grow larger, your configuration may need to span across multiple DeltaV SIS nodes. SIS Network rings and multiple SIS Network domains provide this capability. The following table contains some terminology used in the remainder of SIS Network domain documentation.

Table: SLS 1508 terms and definitions
Term	Meaning
node	The DeltaV I/O Interface Carrier and Logic Solver cards.
SIS Local Peer Bus	A two-channel bus within the DeltaV I/O Interface Carrier.
SISNet Repeater	The device that connects a DeltaV I/O Interface Carrier to another DeltaV I/O Interface Carrier using fiber optic cables. The repeater collects data from Logic Solvers on its node and forwards it around the fiber optic ring. The repeater also takes data off the ring and forwards it to the Logic Solvers on its node.
Redundant Remote Peer Bus (SIS Network ring)	A fiber optic ring that connects DeltaV SIS nodes through SISNet Repeaters. The ring allows Logic Solvers on different nodes to share Secure Parameter data. A DeltaV SIS installation can contain one or more SIS Network rings. You can configure one or more SIS Network domains in a SIS Network ring.
functional group	A set of Logic Solvers used for a single purpose. For example, controlling a single boiler. You define the functional groups in your installation. The DeltaV software does not indicate functional groups within the DeltaV system.
SIS Network domain	A collection of Logic Solvers configured in DeltaV Explorer that can share domain global variables. A SIS Network domain can contain multiple functional groups. Logic Solvers that communicate with each other within a domain must be on the same SIS Network ring. A DeltaV SIS system can have 15 SIS Network domains.
Secure Parameter	This is a Boolean with Status value published by a Logic Solver that can be referenced by another Logic Solver.
Local Publisher	By default, all Logic Solvers are Local Publishers on their node. That is, any Logic Solver module can reference a secure parameter published by any Logic Solver on the same node.
Domain Global Publisher	A Logic Solver whose Secure Parameters can be referenced by another Logic Solver on a different node within the same SIS Network domain, if the Logic Solvers are on the same SIS Network ring. Logic Solvers that are in a different domain cannot reference parameters published by a Domain Global Publisher in another domain even if they are on the same SIS Network ring. Each SIS Network domain can have as many as 32 Logic Solvers configured as Domain Global Publishers.
SIS Network bridge	An Ethernet connection between two SISNet Repeaters in different SIS Network rings.
System Global Publisher	A Logic Solver whose Secure Parameters can be seen by all Logic Solvers in the SIS Network independent of which SIS Network domain they are in. System Global data is sent on the SIS Local Peer Bus, the SIS Network ring, and over the SIS Network bridges to other rings. System Global data is forwarded only from one ring to another so two rings that share data must be connected by a single SIS Network bridge. The entire SIS Network can contain as many as 16 Logic Solvers configured as System Global Publishers.

The following sections show three different ways SIS Network domains and SIS Network rings can be implemented. There are certainly several other ways to configure domains and SIS Network rings, but these three layouts are the most likely you will need. The figures are for illustration only and are not intended to be example configurations. The SIS networks shown are greatly simplified. Actual SIS networks can be much larger.

Using SIS Network domains provides flexibility when configuring large SIS networks. Each domain can have 32 Logic Solvers configured as Domain Global Publishers. That is, any Logic Solver within the domain can potentially receive secure parameter data from these global publishers (subject to the conditions listed below). In addition, the entire DeltaV SIS Network can have 16 Logic Solvers defined as System Global Publishers. Any Logic Solver in the SIS Network can potentially receive secure parameter data from these system global publishers (again, subject to the conditions listed below).

There must be a physical path between the Logic Solver publishing a secure parameter and the Logic Solver referencing the secure parameter. This path required depends on the publisher type:

Local Publisher — All Logic Solvers publish locally on the DeltaV SIS node. Both the publisher and the referencing Logic Solvers must reside on the same DeltaV SIS node.
Domain Global Publisher — Both publishing and referencing Logic Solvers must be on the same DeltaV SIS node or on different nodes connected by SISNet Repeaters on a SIS Network ring.
The nodes containing the publishing and referencing Logic Solvers must be in the same SIS Network domain.
System Global Publisher — Both Logic Solvers must be on the same node, or connected by SISNet Repeaters on a SIS Network ring, or in separate SIS Network rings connected by a single SIS Network bridge connection.

The physical layout you decide to use will depend on the physical layout of your plant (cable runs for fiber optic cable, for example) and process requirements (the possible need to shut down the hardware in one domain without affecting other domains, for example).

There are certainly several ways to configure domains and SIS Network rings, but these three layouts are the most likely you will need. Your SIS Network configuration will depend on the physical layout of your plant and your process requirements.