Mask and Parameters
MASK
Number of phases  Set the number of phases for the NIB. 

Number of Ports  Set the number of Ports of the block. All phase of a single port connects to a single SSN group. 
Port x type  The Number of Ports parameter sets the number of Port x type (where x= 1 to 16) accesible by the user. For each Port x type parameter, 6 different options are possible. 
 
These various options are used to connect different types of SSN groups:  

Examples
Example 1: NIB with IType and VType Interface
Take the following model, ArtemisSSN_simple_switched_case.mdl, which contains a switched inductive source connected to a filter bank.
The model has been separated into 2 SSN groups, with the intersection being defined by the NIB. The NIB interface is Itype in the direction of the capacitor of the filter bank while it is Vtype in the direction of the inductive source. The type of interface is displayed on the block. The NIB also defines the 3 node that will used internally in the nodal part of the SSN solution.
Example 2: NIB with XType Interface, for SSN External Models
The model below simulates a Frequency Dependent Parameter Transmission Line (FDline) based on the model originally developed by Marti. This FDline model is internally coded using the nodal approach and can only produce discrete resistive companion model data like the model discrete admittance and history current sources. The direct inclusion of the line characteristic impedance Zc(ω) into a statespace method would have produced huge ABCD matrices because of the many states that compose Zc(ω).
For this reason, the SSN approach is preferred when the interface of this type of model to the statespace method of SimPowerSystems. To make the interface, the NIB block must have the typeX chosen and connected toward the external SSN model, an FDline model in this case. As previously, the NIB also defines the nodal point of the SSN solution. In this case, 6 nodes will be used in the nodal solution part of SSN.
Input and Outputs
PMtype connectors
Characteristics and Limitations
V and Itype NIB blocks are used to compute the statespace equation of the SSN groups and are internally composed of current or voltage sources. Statespace equation causality restrictions apply to these blocks. This is why Vtype (internal voltage source) connects to inductive groups and Itype (internal current source) to capacitive type groups.
Direct Feedthrough  N/A 

Discrete Sample Time  Yes 
RTLAB XHP Support  Yes 
Work Offline  Yes 