Grass Valley NV9000-SE v.5.0 - Manual (Page 130)

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Virtual Levels and Level Sets
Introduction
Virtual level types are applied when you create actual virtual levels in the process of defining
level sets.
Signals on a virtual level are switched by only one physical level. If your system has multiple
virtual levels of the same name, they are switched by different physical levels.
Conversely, several virtual levels can share a physical level. For example, virtual levels AES 1/2,
AES 3/4, AES 5/6, and AES 7/8 could all be switched by an AES physical level.
 The virtual levels you define are largely for the benefit of control panel operators.
 Virtual level types can be organized into named virtual level groups. The groups are also
considered virtual level types, but types without any particular signal binding. Operators of
certain control panels can choose whether to view levels as a group or as individual levels.
Level Sets
A level set is a set of virtual levels. A level set associates signal types that are normally switched
together (i.e., at the same time).
 Levels are usually defined in the process of creating a level set.
Some systems do not need “level sets.” However, NV9000-SE Utilities requires at least one level
set to be defined. In such a system, that one level set would includes all virtual levels.
In a level set, each virtual level is coupled with a physical level. Signals on that virtual level are
switched by the associated physical level. These couplings also serve to associate the level set
with the particular routers that switch the virtual levels.
The virtual levels in the level set are also ordered. Each level is given a display index in the
ordering. Virtual levels are displayed on control panels according to the ordering of the current
device’s level set, the lowest display index first.
If your system has a single level set, that level set identifies all the virtual levels and references all
the routers used in your system. If there is a physical level (of a router) not included in that single
level set, it cannot be used.
If your system has multiple level sets, together they identify all the virtual levels and reference all
the routers used in your system. If there is a physical level (of a router) not included in those level
sets, the physical level cannot be used.
The name of any virtual level type may be used in multiple level sets, but those names will repre-
sent different virtual levels.
A signal in one level set cannot be routed to a device having the same signal type in another
level set if the physical levels are different, as they would be, for instance, if the physical levels
were in different routers. (A tieline would be required to perform such a route even though the
signal types are otherwise compatible.)
Virtual Level Groups
Virtual level types can be organized into virtual level groups, which are also virtual level types.
A group is defined in the ‘Virtual Level Groups’ table. The group’s name is a special entry in the
‘Virtual Levels’ table. Virtual level groups are intended to appear to the panel operator as if they
were levels.
Groups must be flat in structure, not hierarchical. That is, a group cannot consist of sub-groups.
 NV9000-SE Utilities will let you define hierarchical groups. Avoid doing that!