4-Wire Resistance Measurement using a PXI-4080 and PXI-2503 Switch

[drogers13]

Hello Everyone,

I am designing a program to measure the 4-wire resistance of a low resistance components using a PXI-4080 DMM and PXI-2503 with a TB-2605 connected to it. I am using an example program that performs DMM measurements through handshaking, and I am able to measure the 4-wire resistance when I measure it using just the DMM. When I try to incorporate the switch and TB-2605, the measurements become highly inaccurate. I am not entirely sure I am physically connecting the components correctly, hopefully someone here can provide some insight. 

I have the switch set to the 4 wire 12x1 topology, with following set up:

The programming that I am building will scan through around 6 channels are the read the resistance across different components. From my understanding, when a switch is connected, it should send a signal from the channel out through the com connection into the DMM.