Rockwell Automation 150 USE MN/SMC DIALOG + CONTROLLER - Manual (Page 81)

Calibration 5-3
Calibration Procedure For current measurement accuracy, use the procedure below to
calibrate the SMC Dialog Plus controller to the connected motor. A
clamp-on ammeter, which provides a true rms measurement and has a
published accuracy of ±1% (Fluke model 33 or equal), is required to
perform this procedure.
Notes: (1) If you plan to use the Bulletin 825 converter module for
current feedback to the SMC Dialog Plus controller, this
calibration procedure is not necessary.
(2) An unbalanced three-phase system may affect the
accuracy of the calibration.
(3) It is recommended that Parameter #36, Overload Class,
is programmed to OFF during the calibration procedure.
Calibration requires the motor to be operated at full speed.
Additionally, the motor must be connected to its load in order that the
motor draw as near to its full load current (FLC) rating as possible.
This is necessary so that maximum accuracy is achieved for current
measurements at overload trip levels.
① The currents should measure a minimum of 70% of the motor’s full load current rating in order to
achieve the best results in accuracy.
Description Action Display
1. Check all power and control
wiring connections to the
controller and motor. Apply a start
command to the controller and
check for motor rotation to full
speed.
—
2. Using the clamp-on ammeter,
measure the three-phase motor
currents. Place the ammeter
around the phase with the largest
current draw.
①
—
3. In the Calibrate group, scroll to
the Calibration parameter.
4. Monitor the clamp-on ammeter
and verify that the motor current
is stable. Press the Select key.
Toggle the Up/Down keys to the
Activate setting. Press the Enter
key to accept. Monitor the
ammeter display for the next 2
seconds and record the average
value. During this time period, the
SMC Dialog Plus controller
samples motor response data.
5. Access the next parameter using
the Up key.
6. Press the Select key. Enter the
clamp-on meter value monitored
in step 4. Press the Enter key to
accept. The SMC Dialog Plus
controller is now calibrated.
AT SPEED
###.# AMPS
AT SPEED
###.# AMPS
CALIBRATION
OFF
CALIBRATION
ACTIVATE
ENTER CALIB. AMPS
0.0 AMPS
ENTER CALIB. AMPS
###.# AMPS