Danfoss VLT AQUA Drive Design Manual page 114

6. Application Examples
6.1.3. Potentiometer Reference
Voltage reference via a potentiometer.
6
6.1.4. Automatic Motor Adaptation (AMA)
AMA is an algorithm used to measure the electrical motor parameters of a motor at standstill. This
means that AMA itself does not supply any torque.
AMA is useful when commissioning systems and optimizing the adjustment of the adjustable fre-
quency drive to the applied motor. In particular, this feature is used where the default setting
does not apply to the connected motor.
Par. 1-29 allows a choice of complete AMA with determination of all electrical motor parameters,
or reduced AMA with determination of only the stator resistance, Rs.
The duration of a total AMA varies from a few minutes on small motors, to more than 15 minutes
on large motors.
Limitations and preconditions:
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114
Reference 1 Source
Par. 3-15
Analog Input 53
Terminal 53, Low Voltage
Par. 6-10
= 0 Volt
Terminal 53, High Voltage
Par. 6-11
= 10 Volt
Par. 6-14 Terminal 53, Low Ref./
Feedb. Value = 0 RPM
Terminal 53, High Ref./
Par. 6-15
Feedb. Value
= 1,500 RPM
Switch S201 = OFF (U)
For the AMA to optimally determine the motor parameters, enter the correct motor
nameplate data in par. 1-20 to 1-26.
For the best adjustment of the adjustable frequency drive, carry out an AMA on a cold
motor. Repeated AMA runs may lead to a heating of the motor, which results in an in-
crease of the stator resistance, Rs. Normally, this is not critical.
An AMA can only be carried out if the rated motor current is a minimum of 35% of the
rated output current of the adjustable frequency drive. An AMA can be carried out on up
to one oversized motor.
It is possible to carry out a reduced AMA test with a sine-wave filter installed. Avoid
carrying out a complete AMA with a sine-wave filter. If an overall setting is required,
remove the sine-wave filter while running a total AMA. After completion of the AMA,
reinsert the sine-wave filter.
If motors are coupled in parallel, use only a reduced AMA, if any.
Avoid running a complete AMA when using synchronous motors. If synchronous motors
are applied, run a reduced AMA and manually set the extended motor data. The AMA
function does not apply to permanent magnet motors.
The adjustable frequency drive does not produce motor torque during an AMA. During
an AMA, it is imperative that the application does not force the motor shaft to run, which
is known to happen with windmilling in ventilation systems, for example. This disturbs
the AMA function.
MG.20.N2.22 - VLT
[1] =
® is a registered Danfoss trademark.
VLT ® AQUA Drive Design Guide