Keysight 34931A - Dual 4x8 Armature Matrix for 34980A
The 34931A dual 4x8 armature matrix contains two matrices, each with 32 2-wire crosspoint latching armature relays organized in a 4-row by 8-column configuration. Every row and column are made up of two wires each, a high (H) and a low (L). Each crosspoint relay has a unique channel number representing the row and column that intersects to create the crosspoint. For example, channel 304 represent the crosspoint connection between row 3 and column 4 (all columns consisting of two digits; in this case the digits are 04).
You can connect any combination of inputs and outputs at the same time. However, only Matrix 2 in this module connects to the Analog Buses. By closing channels 921 and 922 you can connect rows 5 and 6 respectively to the internal DMM of the 34980A mainframe for voltage and resistance measurements. You can connect multiple matrix modules externally and/or through the Analog Buses for applications that require large matrices.
When the power is off, matrix relays maintain state, and Analog Bus relays open.