Using Proper Grounding - Fluke 123 User Manual

Using Proper Grounding

Incorrect grounding can cause various problems. This
Section gives you guidelines for proper grounding.
Use the short ground lead(s) when measuring DC or
AC signals on input A and input B. (See Figure 3-2.)
To avoid electrical shock or fire, use only one
COM (common) connection
all connections to COM
potential.
Use the unshielded black ground lead to COM
(common) for Ohm (Ω), Continuity, Diode, and
Capacitance measurements. (See Figure 3-3.)
Using the unshielded ground lead is also possible for
single or dual input measurements for waveforms with a
frequency up to 1 MHz. This may add some hum or
noise to the waveform display due to the unshielded
ground lead.
Warning
, or ensure that
are at the same
Tips and Troubleshooting
Figure 3-2. Grounding with Short Ground Lead
Figure 3-3. Grounding with Unshielded Ground Lead
Using Proper Grounding
3
59