Application Note

3 Fluke Corporation Stepping up to power quality tools
The Fluke 43B Menu screen provides a quick view of instrument
functions.
Both voltage and current waveforms appear on the Volts/Amp/Hertz
screen.
The Volts/Amps/Hertz function
Begin use of the Fluke 43B by depressing the
Menu key and observing the instrument menu.
Select the Volts/Amps/Hertz function and press
Enter. Both voltage and current waveforms appear
on the screen. A few quick checks here can deter-
mine whether you are at a location in the system
that may be presenting some power quality con-
cerns. Notice the severity of any distortion on the
voltage and current sine waves. Look for a crest
factor (CF) of 1.4 on the voltage sine wave. Crest
factor is the ratio of peak voltage to rms voltage. A
CF of less than 1.4 indicates the voltage is flatten-
ing out across the top of the sine wave. This may
cause computer lock-ups and other intermittent
problems with electronic loads being supplied.
The Power function
Return to the menu screen and select the
Power function. Notice that the analyzer has
the capability of measuring either single-phase
or three-phase power. If three-phase power is
selected, the instrument shows how to connect
test leads for such measurements. The Power
screen also displays the voltage and current sine
waves in addition to power measurement values
of kilowatts (kW), kilovolt ampere (kVA), kilovolt
ampere reactive (kVAR), power factor (PF), dis-
placement power factor (DPF), and hertz (Hz). The
Power function can be a valuable tool as part of
an energy management program when used to
help determine operational cost of specific pieces
of equipment.
Select the VOLTS/
AMPS/HERTZ
function and press
Enter for a quick
look at system
voltage and current
sine waves.
RMS voltage value
Crest factors less
than 1.4 indicate
potential problems
Voltage sine wave
Single-phase
amperage
Current sine wave
indicates current
being drawn by
nonlinear type
loads
Multiplying this
kW reading by
the number of
hours of opera-
tion can be used to
calculate the cost
of operating this
compressor
Power factor in
this single-phase
reading is 1.00 at
60 Hz
Current sine wave
indicates current
is linear and in-
phase with voltage
The Power screen provides voltage and current sine waves in addi-
tion to the power readings for this compressor motor.