Fluke 377 - AC;DC Voltage Measurement with Leads; Resistance and Continuity Measurement

377/377 FC/378/378 FC
Users Manual
14
Capacitance
The Clamp determines capacitance by charging a capacitor with a
known current, measuring the resulting voltage, then calculating
the capacitance.
Note
A good capacitor stores an electrical charge and may
remain energized after power is removed. Before you
touch the capacitor or make a measurement, turn all
power OFF, use the Clamp to confirm that power is
OFF, and carefully discharge the capacitor by
connecting a resistor across the leads. Be sure to wear
appropriate personal protective equipment.
To test capacitance:
1. Turn the control knob to
D.
2. Push
B to shift to the t function.
3. Remove the capacitor from the circuit and discharge the
capacitor.
4. Connect the black test lead to the COM terminal and the red
test lead to the VX terminal.
5. Touch the probes to the capacitor leads.
The display shows the measurement.
OL indicates the capacitor is faulty or the capacitance value is
higher then the measurement range. diSc indicates the
capacitor does not properly discharge.
DC Current
To measure dc current:
1. Turn control knob to Y.
2. Push
B to compensate for outside influences.
The display shows
C to indicate that the measurement is
from the jaw. When the current measurement is <0.5 A, the
center dot in the icon flashes. For current measurements
>0.5 A, the center dot in the icon is steady.
iFlex Probe
XW Warning
To avoid electrical shock, do not apply or remove
from live hazardous conductors.
The high-performance AC Flexible Current Probe uses the
Rogowski principle for accurate, non-intrusive measurement of
sinusoidal, pulsed, and other complex waveforms. The flexible and
lightweight measuring head allows quick and easy installation in
hard-to-reach areas and works well with large conductors.
To use the iFlex Probe:
1. Connect the iFlex Probe to the Clamp. See Figure 3.
2. Connect the flexible part of the iFlex Probe around the
conductor. If you open the end of the iFlex Probe to make the
connection, make sure that you close and latch the coupling.
See the detail in Figure 3. You should be able to hear and feel
the lock snap into place.
Note
When you measure current, center the conductor in
the iFlex Probe. Avoid measurements close to other
current-carrying conductors.