Variable Speed Motors - Chauvin Arnoux F 1N Mode D'emploi

6 Repeat the operation for each phase of the motor. The current imbalance may be due to
imbalance of the voltage or to a short-circuit on the winding of the motor.
(Model F3N) :
7 The RECORD mode, if activated, will record the inrush current of the motor. When the
motor has reached its rated speed, press the HOLD button to stop the recording, then
press the MIN/MAX button to read the MAX, MIN and AVG reached since engaging
RECORD mode.

VARIABLE SPEED MOTORS

In addition to current measurements on motors, the
increasingly more common use of electronic power
control systems which change motor speeds involve
special measurements for checking the correct
operation of the Motor/Control assembly.
We list the most important measurements:
Checking motor speed (this depends on
frequency) simultaneously against the instruc-
tion point output by the variable speed control.
Measure the rated current of the motor (compa-
red to the control assembly instruction point).
Check the stability of the Frequency/Current
ratio during changes in speed.
Check the effective limitation of the motor inrush
current (by the variable speed control) by
comparison with the specifications given by
the manufacturer.
1 Press the ON/OFF button to switch on the clamp.
2 Position the clamp around one of the phase
conductors.
3 Read the trms current value and compare it with the instruction point output by the control
assembly.
4 Press the Hz button, vary the speed of the motor, and compare the reading on the digital display
of the clamp with the instruction point of the control assembly.
5 At the same time read the trms current on the bargraph.
During the variation in speed check that the Frequency/Current ratio remains constant (it depends
on the type of variable speed control used, refer to the specifications given by the manufacturer).
Variable speed control
Phases
46
Neutral