Amprobe ACD-330T Clamp-On-Multimeter - Manual (Page 29)

AC MOTOR CURRENTMEASUREMENT
You can measure starting (inrush) current, running current, and current imbalance in
AC Motor circuits. Inrush current is typically 6-8 times the value of running current,
depending on the motor type.
1) Set the rotary switch to " A ".
2) Press and hold the PEAK button (>lsec) to enter 1 ms PEAK hold mode.
3) Clamp around a motor phase conductor. Be sure the clamp jaws are completely closed,
or measurement will not be accurate.
4) Press ZERO button to set the display to zero.
5) Turn the motor on. When the motor gets to the desired speed, observe the display for
inrush current reading.
6) If the reading is " OL", you can push the RANGE button momentarily to change meas-
uring range. Turn off the motor.
7) Repeat your measurement from step 2 through 6 for each phase. A voltage imbalance
or a shorted motor winding may cause imbalanced current.
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