4x128, 1-wire, 250 V/1 A Matrix. The EX1200-4128 is an ultra high-density matrix module that allows the user to connect any input row to any output column with an SPST relay at every row/column crosspoint. This architecture provides the framework for flexible switch system designs where multiple test instruments need to be connected to common test points. The one-wire architecture allows for any of the 128 row inputs to be connected to any of the 4 column outputs. The four output columns can be routed to the EX1200 series internal analog backplane to build large matrices or to connect to the optional 6.5 digit DMM. A (4 x 768) 1-wire matrix can be accommodated in a 1U EX1200 mainframe.