Instruction manual 91/121 V6.3
Commissioning
Speed loop prop
Minimum Maximum
Units of measure
0
999,99
-
Set the proportional gain of the speed loop: the larger the number is, the faster the motor is in response, but the instability of the regu -
lator is at risk. For the adjustment of this parameter it is recommended to start from a low number (2.0, 3.0) and then, after enabling
the motor and rotating it, gradually increase it until it is possible without making the system unstable.
Speed loop int
Minimum Maximum
Units of measure
0
999,99
-
Set the additional gain of the speed loop: the larger the number, the more the motor quickly resets the speed error (difference between
the required speed and the actual speed), but the instability of the regulator is at risk. For the adjustment of this parameter it is recom-
mended to start from a low number (0.01, 0.02) and then, after enabling the motor and rotating it, gradually increase it until it is pos -
sible without making the system unstable.
An.Inp.1 Gain
Minimum Maximum
Units of measure
-2.00
+2.00
-
Set the multiplication factor of the signal coming from the analog input 1. With this parameter it is possible to scale the voltage signal
connected to the analog input in order to adapt it to reach the maximum speed.
Example:
suppose we want to reach a maximum speed of 3000 RPM when the speed signal connected to the analog input 1 is at its
maximum value; unfortunately, the speed signal coming from the CNC has a full scale of 8.5 Vdc. You can calculate the scale value to
amplify it and thus get the maximum speed with 8.5V instead of 10V:
Gain
=
10
V
MAX
V
max
= Maximum voltage of the speed reference.
Gain = Gain of the analog input.
Substituting in the formula the bottom scale value of the example (8,5V) is calculated that the gain to be set in this parameter is 1.17.
An.Inp.1 Offset
Minimum Maximum
Units of measure
-10.00
+10.00
%
Set the offset of the analog signal 1. For the adjustment of this parameter it is recommended to give a speed reference “0” and then to
enable the drive; if the motor rotates slowly, act on this parameter to stop the rotation.
An.Inp.1 Sign
With this parameter you can select whether to reverse the sign of the analog input 1 or to leave it as originally. The possible selections
are:
•
NORMAL: The “Value” signal indicates exactly the value of the analog input 1.
•
REVERSE: The “Value” signal indicates the value of the analog input 1 inverted of sign.
See Drawing 15 on page 40 for clarity.
An.Inp.1 Value
Minimum Maximum
Units of measure
-100.00
+100.00
%
Read-only parameter indicating the output signal from the analog input compensation block 1. See drawing 15 on page 40 to figure
out where this parameter works in the calculation.
NOTE:
A value of 100 % does not mean that the analog input is 10V; this also depends on the value of the gain and the offset. In
the example above given that the gain is set to 1.17 then the “Value” will indicate 100 % when the analog input is 8.5V as calcu-
lated.
Speed Ramp Time
Minimum Maximum
Units of measure
0.1
650.0
Sec
Parameter to set the up/down time of the speed ramp. Assuming an input of 0 to 100 % of the value is given, this parameter is defined
as the time it takes (“Speed Demand”) to go from 0 % to 100 %.
Therefore if the input step goes from 0 % to 50 % it will mean that the time taken to finish the ramp will be half the time set on this
parameter.
Alter Elettronica s.r.l.
39
