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2-50
IM DL350-03EN
2.15 Connecting a Logic Probe to the Instrument’s Logic Input Terminal or the Logic Input Module
Connecting Logic Probes
Logic Probes (702911, 702912) and High-Speed Logic Probe 700986
1.
Attach the connecting lead (IC clip or alligator clip) that came with the logic probe, and push
the logic probe levers inwards to lock the connector into place. To remove the connecting leads
from the logic probe, push both of the levers outwards. Proceed to step 3.
Isolated Logic Probe 700987
1.
Connect the measurement leads to the logic probe’s input terminal.
2.
Set the input switch. When you set it to AC, the threshold levels are 50 VAC ± 50% (Hi: 80 VAC
to 250 VAC, Lo: 0 VAC to 20 VAC); when you set it to DC, the threshold levels are 6 V ± 50% (Hi:
10 VAC to 250 VDC, Lo: 0 VAC to 3 VDC).
Connecting the Logic Probe to a Logic Input Module
3.
Turn the instrument’s power switch off.
4.
Connect to the logic signal input connector of the logic input module (720230) the end of the
logic probe’s 26-pin connector that has a clamp filter (ferrite core; part number: A1190MN).
5.
Turn on the instrument.
To the logic signal input connector
of the logic input module
Note
• When a logic probe is not connected to the instrument, each bit is indicated as being at the high level.
• For the logic probe specifications, see section 6.14, “Logic Probe Specifications.”
• The logic input display is turned off by default. For information about turning the display on and off, see
section 2.9, “Configuring Logic Signal Measurements,” in the User’s Manual.
• Before using logic probes (702911, 702912) or isolated logic probe 700987, flip the attenuation switch
back and forth several times. The switch’s electrical contacts can weaken if not used for long periods of
time.