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USB-9211/9211A User Guide and Specifications
Wiring the USB-9211/9211A
The USB-9211/9211A has a 10-terminal, detachable high voltage screw 
terminal enclosure that provides connections for four thermocouple input 
channels. Each channel has a terminal to which you can connect the 
positive lead of the thermocouple, TC+, and a terminal to which 
you can connect the negative lead of the thermocouple, TC–. The 
USB-9211/9211A also has a common terminal, COM, that is internally 
connected to the isolated ground reference of the module.
Caution
The high voltage screw terminal backshell must be installed when using 
hazardous voltages (>42.4 V
pk
, 60 VDC).
If you are unsure which of the thermocouple leads is positive and which is 
negative, check the thermocouple documentation or the thermocouple wire 
spool. If you are using shielded wiring, connect one end of the shield to the 
COM terminal.
Figure 6.  Connecting a Thermocouple Input Signal to the USB-9211/9211A
Thermocouple
TC–
TC+
Shield
USB-9211/9211A
COM