Subnetwork Controllers

In the electric domain network, the most common use of a subnetwork controller is to represent a distribution feeder source. It is a special feature that functions as a proxy for the point that power enters the electric network. It energizes a group of interconnected electric distribution facilities known as a feeder. Subnetwork controllers can also be used as the grouping principle for other collections of interconnected features, such as transmission circuits, low voltage networks, or the facilities belonging to a high or medium voltage (HV/MV) substation. Subnetwork controllers are similar for either the balanced or unbalanced model. One exception is that in a balanced model, the low voltage subnetwork source can be at a fuse.

Recommended Configuration

A circuit breaker connected to a bus on the MV side of an HV/MV substation transformer is often chosen as a feeder source in the ArcFM UN. In some cases, a recloser serves as a feeder source.
Use a separate AssetGroup AssetType pair designation for a circuit breaker that serves as subnetwork controller and one that does not.

Required Configuration

It must be a two-terminal feature in the devices feature class of the electric domain network.
Non-spatial subnetwork controllers are not currently supported by the ArcFM XI series of applications.
The feature’s terminal configuration must be directional where one of the two terminals is designated as the upstream terminal.
The feature cannot be a transformer because of a conflict of interest between the role of the subnetwork controller and the role of a voltage-altering device in a voltage propagation scheme.
The feature is in a class by itself and it cannot share AssetGroup and AssetType with non-subnetwork controller equipment types in the ArcFM UN. If a circuit breaker must serve as a subnetwork controller, then it must have a different AssetGroup AssetType from a circuit breaker that is not a subnetwork controller.
The feature’s AssetType network category is E: Subnetwork Controller.
Subnetwork controllers in the ArcFM UN unbalanced electric model are different from regular switchable device banks because the subnetwork controller device bank does not require units. Circuit breakers, or reclosers, at this high level of the distribution system tend to be symmetrical with respect to the three power phases, except for the switch state (open or closed) for each phase. The phase-specific switch state for a subnetwork controller, in this case PhasesNormal, can be effectively modeled for phase propagation in the UN. This attribute means the DeviceStatus attribute is not needed because the subnetwork controller is the starting point of the propagation.
If a subnetwork controller device has phase-specific attributes other than DeviceStatus, it must contain units to represent each phase. If a subnetwork controller bank device contains units, those units cannot be connected to anything in the network topology. The terminals of the subnetwork controller in the UN help with network functions such as tracing, propagation, and UpdateSubnetwork. If the subnetwork controller has units, it must have the network category of E:Has Disconnected Units.
In a balanced, low-voltage network model, a fuse can be used as a subnetwork controller.

Subnetwork Controller Network Category

This category is used to discriminate between types that can or cannot serve as a subnetwork controller.