Potentiometer Reference; Automatic Motor Adaptation (Ama); Smart Logic Control; Smart Logic Control Programming - Danfoss VLT HVAC Design Manual

Application Examples

6.1.3 Potentiometer Reference

Voltage reference via a potentiometer.
3-15 Reference 1 Source [1] = Analog Input 53
6-10 Terminal 53 Low Voltage = 0V
6-11 Terminal 53 High Voltage = 10V
6-14 Terminal 53 Low Ref./Feedb. Value = 0 RPM
6-15 Terminal 53 High Ref./Feedb. Value = 1.500
RPM
Switch S201 = OFF (U)
6 6
Speed RPM
P 6-15

6.1.4 Automatic Motor Adaptation (AMA)

AMA is an algorithm to measure the electrical motor
parameters on a motor at standstill. This means that AMA
itself does not supply any torque.
AMA is useful when commissioning systems and
optimising the adjustment of the frequency converter to
the applied motor. This feature is particularly used where
the default setting does not apply to the connected motor.
1-29 Automatic Motor Adaptation (AMA) allows a choice of
complete AMA with determination of all electrical motor
parameters or reduced AMA with determination of the
stator resistance Rs only.
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:
•
For the AMA to determine the motor parameters
optimally, enter the correct motor nameplate
data in 1-20 Motor Power [kW] to 1-28 Motor
Rotation Check.
•
For the best adjustment of the frequency
converter, carry out AMA on a cold motor.
Repeated AMA runs may lead to a heating of the
motor, which results in an increase of the stator
resistance, Rs. Normally, this is not critical.
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VLT HVAC Drive Design Guide
39 42 50 53 54
Ref. voltage
P 6-11 10V
1 kW
MG11BB02 - VLT
•
AMA can only be carried out if the rated motor
current is minimum 35% of the rated output
current of the frequency converter. AMA can be
carried out on up to one oversize 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
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
55
apply to permanent magnet motors.
•
The frequency converter 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 e.g. wind milling in ventilation systems. This
disturbs the AMA function.
•
AMA can not be activated when running a PM
motor (when 1-10 Motor Construction is set to [1]
PM non salient SPM).

6.1.5 Smart Logic Control

A useful facility in the VLT
converter is the Smart Logic Control (SLC).
In applications where a PLC is generating a simple
sequence the SLC may take over elementary tasks from the
main control.
SLC is designed to act from event send to or generated in
the frequency converter. The frequency converter will then
perform the pre-programmed action.

6.1.6 Smart Logic Control Programming

The Smart Logic Control (SLC) is essentially a sequence of
user defined actions (see 13-52 SL Controller Action)
executed by the SLC when the associated user defined
event (see 13-51 SL Controller Event) is evaluated as TRUE
by the SLC.
Events and actions are each numbered and are linked in
pairs called states. This means that when event [1] is
fulfilled (attains the value TRUE), action [1] is executed.
After this, the conditions of event [2] will be evaluated and
if evaluated TRUE, action [2]will be executed and so on.
Events and actions are placed in array parameters.
Only one event will be evaluated at any time. If an event is
evaluated as FALSE, nothing happens (in the SLC) during
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HVAC Drive frequency