Switch Banks and Units

Bank and Unit Definition

A switch bank represents the spatial location of the switchable device. It can be contained and have units but are not required.

Units are used to represent the individual piece of equipment inside the bank. It must be connected and contained in an unbalanced network. Units are not required in a balanced network, but if present, they must be contained.

Balanced vs Unbalanced Network Review

The unbalanced network model is used in North America and the banks represent the physical location of the equipment. They can have asymmetrical or symmetrical phase voltage modeling. Phasing is represented on the individual equipment.

The balanced network model is used in Europe and the banks represent the physical location of the equipment. This model only allows symmetrical phase voltage modeling and the phasing is represented on the bank.

Required Configuration — Unbalanced

For a switchable device that uses phases on the units and is a part of the unbalanced model, we distinguish between three-phase switchable devices that may have a different status (open/closed) on one phase than on another.

• ​The E:Has Connected Units network category is used to distinguish between a “bank” type switch device in the ElectricDevice feature class and a device type switch device in the Electric JuctionObject table. A switch bank must belong to the E:Has Connected Units category, and a switch device must not. 

• ​If units are needed to support an Asset Management System:

  • The E:Has Disconnected Units network category is used.

  • ​Set the TerminalPath attribute to All.

• ​If no units are needed:

  • Do not assign an additional network category.

  • ​Set the TerminalPath attribute to All.

• Both types have two terminals and a bidirectional terminal configuration where neither terminal is intrinsically upstream of the other, but differ in their terminal path configuration. An example is whether or not a direct internal path exists between the two terminals of the device​. 

• ​The bank devices have none listed for their terminal paths configuration. The terminals can only be connected to each other with other network entities. 

• ​In a bank feature, other entities are the non-spatial junction objects, called a switch unit, that represent the units of the bank. Each unit object in this arrangement represents a single-phase operable device that is considered internal to the bank and each unit has its own independent DeviceStatus attribute value (open/closed). The continuity of each phase through the bank is a function of the individual switch states of its units.  

• ​The one phase and gang devices do not require independently operable units on each phase, so the continuity of power through the device feature depends only on the DeviceStatus attribute (open/closed) of the device feature itself, which controls all phases at once. This arrangement can be simply modeled by declaring a direct path connecting the two terminals of the device feature. 

Required Configuration — Balanced

For a switchable device that uses phasing on the units and is a part of the balanced network model, the three gang-operated phases must be the same for all phases of the device.

• ​Must have a bidirectional terminal configuration where neither terminal is intrinsically upstream of the other.

• ​The bank devices have none listed for their terminal paths configuration. The terminals can only be connected to each other with other network entities. 

• ​In a bank feature, other entities are the non-spatial junction objects, called a switch unit, that represent the units of the bank. Each unit object in this arrangement represents a single-phase operable device that is considered internal to the bank and each unit has its own independent DeviceStatus attribute value (open/closed). The continuity of each phase through the bank is a function of the individual switch states of its units.  

• ​If a switchable device is gang operated, an attribute should be added to the ElectricDevice feature.