©
National Instruments Corp.
11
NI 9237 Operating Instructions and Specifications
Wiring TEDS Channels
Ens
u
re that neither the TEDS data (T+) nor the TEDS ret
u
rn (T–)
signal is tied in common to any AI signals on the NI 9237. The
NI 9237 connects all the T– signals together internally. Visit
ni.com/info
and enter the info code
rdted
s
for more
information abo
u
t TEDS sensors.
NI 9237 Connection Options
Wiring resistance can create errors in bridge circ
u
its. The NI 9237
provides two mechanisms to correct for these errors: remote
sensing and sh
u
nt calibration.
Remote Sensing
Remote sensing contin
u
o
u
sly and a
u
tomatically corrects for errors
in excitation leads, and generally is most appropriate for half- and
f
u
ll-bridge sensors.
Long wire and small ga
u
ge wire have greater resistance, which can
res
u
lt in gain error. The resistance in the wires that connect the
excitation voltage to the bridge ca
u
ses a voltage drop, which is a
so
u
rce of gain error. The NI 9237 incl
u
des remote sensing to
compensate for this gain error. Connect remote sense wires to the
points where the excitation voltage wires connect to the bridge
