382075 V2.2V 9/10
11
Once the NEXT button is pressed (after measurements of W
RS
(or W
L1L2
) and W
TS
(or
W
L3L2
), the power clamp will add the two values and display the result on the LCD. The
WRST symbol appears indicating that the reading shown is the wattage of the 3
φ
3W
unbalanced Power. PF is not shown in the 3
φ
3W unbalanced power mode.
NOTE:
Once a phase is selected as the COMMON connection, users cannot
change this selection in the subsequent measurements. For example, if S (or L2)
phase is selected, S (or L2) phase is always connected to the COM of the power
clamp during measurements of W
RS
(or W
L1L2
) and W
TS
(or W
L3L2
) in 3
φ
3W
unbalanced power mode.
NOTE:
The "+" sign printed on the jaw must face the power source.
NOTE:
In the 3
φ
3W unbalanced power measurement mode, W
RS
or W
TS
could
be a negative value. Users must make sure all the connections are correct to
obtain correct power readings.
3
φ
4W Unbalanced Power Measurements
W
3
φ
W
=
W
RST
=
W
R
(
L1
)
+
W
S
(
L2
)
+
W
T
(
L3
)
The measurements of W
R(L1)
, W
S(L2)
, and
WT(L3)
are required for these measurements.
1. Measure W
R(L1)
a.
Apply power to the meter with the jaw clear of any conductors.
b.
Set the rotary switch to the 3
φ
position.
c.
Press the 3
φ
button twice, and the 3
φ
4W symbol appears singularly on the left side
of the LCD. The W
R
symbol will flash prompting the user to take the W
R
.
measurement
Note: If the watt reading is not zero, press the DCA/DCW ZERO button once to zero
reading
d.
Insert the test leads into the input terminals
e.
Connect the neutral line to the COM (black) terminal.
f.
Connect the V (red) test lead to the first phase R ( L1).
g. Clamp on to the same phase R (L1).
h. The power clamp meter will automatically select the proper range.
i.
Wait until the reading is stable, then press the NEXT button. The W
R
symbol will
disappear. Now, W
R
is stored in the memory, and the W
S
symbol flashes
prompting the user to take the W
S
measurement.
