Unidrive M700/M701 / Unidrive HS70/HS71 Control Getting Started Guide 43
Issue Number: 2
Safety information Introduction Control connections Getting started
Basic parameters 
(Menu 0)
Running the motor
Further information
6.2.5 RFC-S mode (Sensorless)
Permanent magnet motor without position feedback
Action Detail
Before power-
up
Ensure:
• The drive enable signal is not given (terminal 31).
• Run signal is not given
• Motor is connected
Power-up the 
drive
Verify that RFC-S mode is displayed as the drive powers up. If the mode 
is incorrect see section 4.7
Changing the operating mode on 
page 20, otherwise restore parameter defaults (see section 
4.9
Restoring parameter defaults on page 21).
Ensure that the drive displays ‘inhibit’ 
Enter motor 
nameplate 
details
Enter:
• Motor rated current in Pr 00.046 (A)
Ensure that this equal to or less than the Heavy Duty rating of the 
drive otherwise ‘Motor Too Hot’ trips may occur during the autotune.
• Number of poles in Pr 00.042
• Motor rated voltage in Pr 00.044 (V) 
Set maximum 
speed
Enter:
• Maximum speed in Pr 00.002 (rpm)
Set 
acceleration / 
deceleration 
rates
Enter:
• Acceleration rate in Pr 00.003 (s/1000 rpm)
• Deceleration rate in Pr 00.004 (s/1000 rpm) (If braking resistor 
installed, set Pr 00.015 = Fast. Also ensure Pr 10.030, Pr 10.031 
and Pr 10.061 are set correctly, otherwise premature ‘Brake R Too 
Hot’ trips may be seen).
Autotune
The drive is able to perform a stationary autotune. The motor must be at 
a standstill before an autotune is enabled. A stationary autotune will give 
moderate performance.  
• A stationary autotune is performed to locate the flux axis of the 
motor. The stationary autotune measures the stator resistance, 
inductance in flux axis, inductance in torque axis with no load on the 
motor and values relating to deadtime compensation from the drive. 
Measured values are used to calculate the current loop gains, and 
at the end of the test the values in Pr 00.038 and Pr 00.039 are 
updated. 
To perform an autotune:
•Set Pr 00.040 = 1 or 2 for a stationary autotune. (Both perform the 
same tests).
• Close the run signal (terminal 26 or 27).
• Close the drive enable signal (terminal 31). The upper row of the 
display will flash 'Auto Tune' during the test.
• Wait for the drive to display 'Ready' or 'Inhibit'.
If the drive trips it cannot be reset until the drive enable signal (terminal 
31) has been removed.
• Remove the drive enabled and run signal from the drive.
Check 
Saliency
In sensorless mode, when the motor speed is below Pr 
00.045
 / 10, a 
special low speed algorithm must be used to control the motor. There are 
two modes available, with the mode chosen based on the saliency of the 
motor. The ratio No-load Lq (Pr 
00.056
) / Ld (Pr 
05.024
) provides a 
measure of the saliency. If this value is > 1.1, then Non-salient mode 
must be used (this is the default), otherwise Injection mode may be used. 
Set Pr 
00.054
 for the selected mode: Injection (0) or Non-salient (1).
Save 
parameters
Select 'Save Parameters' in Pr 
mm.000
 (alternatively enter a value of 1000 
in Pr 
mm.000
) and press red   reset button or toggle the reset 
digital input. 
Run Drive is now ready to run
Model No: 95UXXXXXXXX XXXX
Volts:   380/480
Cont:   7.7Nm:4.81Arms
Stall:    9.5Nm:5.91A rms
Speed: 3000rpm Poles:6
Kt:       1.6Nm/Arms
Ins Class: H
Brake: 12Nm
24V
0.67A
Serial No: XXXXXXXXXXX
Control Techniques
Dynamics Ltd
ANDOVER, HANTS.
ENGLAND. SP10 5AB
Unidrive M700_M701 Getting Started Guide English iss7.book  Page 43  Friday, December 12, 2014  1:14 PM