The hardware implementation of DeltaV Zones requires the addition of an Inter-Zone Server (IZS) in each DeltaV system. The Inter-Zone Servers are then connected by an Inter-Zone Control Network (IZCN). The only function of the Inter-Zone Servers and their network is to communicate Inter-Zone operating data between systems.
Each IZS node must have:
- a network interface connection (NIC) (two for redundant communications) for DeltaV network
- a network interface connection (two for redundant communications) for the Inter-Zone Control Network
The following figure shows a simple example of a DeltaV Zones implementation connecting two DeltaV systems. The purpose of this diagram is to show how the Inter-Zone Servers connect to the DeltaV network and to each other. The diagram is not intended to be a recommended configuration.
As the figure shows, a DeltaV zone is a DeltaV system that includes an Inter-Zone Server. That is the only difference between a zone and a system.
A more advanced implementation of zones is shown in the following figure. This network includes redundancy in both DeltaV networks and in the Inter-Zone Control Network. The figure also includes a plant network as well. Note that OP_STA_A and OP_STA_B have been configured as Remote Desktop Services servers and PPLUS_A and T_CLIENT_1 have been configured as Remote Desktop Clients. With the system configured as shown, ZONE_B can be configured from ZONE_A, ZONE_A cannot be configured from ZONE_B, and both zones can be configured from the remote client T_CLIENT_1.
Redundant IZSs switch over only when DeltaV ACN network communication is lost. Redundant IZSs do not switch over when Inter-zone communication is lost. Verify that zones are communicating by monitoring the zone and IZS integrity diagnostics parameters or assigning these integrity parameters to alarms.
In systems with redundant Inter-Zone Servers, there is a loss of communications for several seconds after an IZS switchover occurs. During this delay, external references in modules are affected. The .CV values are Hold Last Value and .ST values are BadNoCommLUV (numeric value 24). This delay can last as long as 30 seconds.
You should consider this delay when configuring control strategies with control across zones.
After implementing DeltaV Zones you can perform non-control functions between DeltaV systems using standard Windows network support functions over a separate plant or non-control network. The DeltaV workstations that use the plant network must have sufficient Domain trust relationships in place. All workstation names must be unique among all connected DeltaV systems (no duplicate workstation names anywhere within the zones).
Interconnected zone hardware must all be in the same time zone and have the same installed language choice.
The only DeltaV menu options on an IZS are:
If your DeltaV systems are configured as workgroups and you need to add users who can log in to the IZS, do the following:
- From the DeltaV User Manager on another workstation in the system, create the users.
- Use Replicate Account to copy the account to the IZS.
- Close the DeltaV User Manager.
- Download the workstation.
- Download the IZS.
The user accounts now exist in the IZS.
If you are connecting DeltaV systems that are configured as domains, each system must have a unique domain name.