Agilent Technologies manual 5Floating signal source configuration in U2802A

2 Features and Functions

Bypass mode: In bypass mode, the TCn+ input is routed directly to the corresponding AI channel on Rear Connector 1. The single- ended signals tied to TCn+ should be referenced to a GND pin, and not to the TCn– input, as it is not directly connected to GND. The signal connection will depend on the type of source used.

For floating signal sources, all input signals are connected to the ground in the U2802A as illustrated in Figure 2- 3. However, it is not recommended to tie ground- referenced signal sources in this manner. Any potential differences between the signal source ground and the U2802A ground could potentially induce excessive current to flow through the ground wires causing the wires and module to be damaged.

Figure 2-5Floating signal source configuration in U2802A

For ground- referenced signal sources and differential signal sources, the configuration in Figure 2- 6 is recommended. Take note that the corresponding DAQ channel will need to be configured as a DIFF input to enable this type of connection.

32 Agilent U2802A 31-Channel Thermocouple Input User’s Guide