5
Application Examples
102
Keysight U1401B User’s and Service Guide
Simulating a 2-wire transmitter on a current loop
The special yellow test lead supplied with the U1401B can also be used for
simulating a 2-wire transmitter. This lead is used in place of the red lead (which is
used in most other applications). It protects the instrument from high loop
voltages, and it also has the advantage of using the same two output terminals
for all applications.
1
Turn the rotary switch to any one of the
/
or
/
positions.
2
Connect the special yellow test lead between the positive output terminal of
the instrument and the input terminal of the measurement device on the
current loop. Refer to
3
Connect the black alligator lead between the negative output terminal of the
instrument and the current loop excitation source. Make sure the polarity is
correct.
4
Set the current level between 0 mA and 20 mA. Do not set a negative current
output value.
5
Press
OUTPUT
to output the test current.
This connection can be used for any loop voltage from 12 V to 30 V.
CAUTION
Do not apply an external voltage exceeding 30 V across the output terminals
of the instrument.
