The dual point matrix is one possible topology of test points inside a test system. In the dual point matrix one relay with one inductor controls two contacts respectively test points (while in a single point matrix one relay is allocated to one single test point). The selection of the individual test points follows a decoding, which is available on the test point card.
Compared to a single point matrix the test point module contains less components and needs less space. The production costs are significantly lower. In addition, energy consumption and heat emission are lower.
At some special test steps (e.g. when a bundle of wires is simultaneously tested for its insulation resistance) a dual point matrix can limit the options for the assignment of test points. During adaption, definition of the pin table and development of test steps in the editor it needs to be assured, that two individually switched test points may not be tested at pins that are switched by the same relay.
Generators and measurement units are independent from the type of the switching matrix.